Israeli strikes and demolitions have destroyed dozens of buildings in areas of Gaza City, satellite images show, as the Israel Defense Forces (IDF) said its offensive has established control over 40% of the city.

The new images reviewed by BBC Verify show that intensive bombardments and controlled explosions have levelled several neighbourhoods over the past four weeks.

Rows of tents – which have sprung up over the city to shelter Palestinians displaced by the Israeli military campaign – have also disappeared over the past month, the images show.

Prime Minister Benjamin Netanyahu announced Israel’s intention to seize all of the strip and launch an incursion into Gaza City after indirect talks with Hamas on a ceasefire and hostage release deal broke down in July.

UN humanitarian officials have warned that the impact of a full-blown offensive would be “beyond catastrophic”. Strikes have intensified in areas of Gaza City in recent weeks and dozens of Palestinians have been killed in attacks this week alone according to the Hamas-run health ministry and civil defence agency.

Satellite images show that significant damage has already occurred in Gaza City’s Sheikh Radwan, Zeitoun and Tuffah neighbourhoods in recent weeks. The photos show that dozens of buildings in the city were levelled between August and September.

In a statement to BBC Verify, the IDF said it was “locating and destroying terror infrastructures embedded, among other things, inside buildings”.

In Sheikh Radwan – a neighbourhood located about three kilometres from Gaza City centre – a number of buildings have been wiped away. BBC Verify previously geolocated footage of strikes carried out by the IDF to the area on 29 August.

The images clearly show track marks left by Israeli armoured vehicles, many of which pass through sections of the neighbourhood where buildings and trees once stood.

BBC Verify also geolocated footage of an explosion which levelled dozens of high-rise buildings as part of a demolition in the adjacent Jabalia area.

The footage, which first appeared online on 31 August, mirrors similar demolitions carried out by Israeli forces in southern Gaza. Thousands of buildings in areas including Rafah and Khan Younis have been demolished by controlled explosions and demolition contractors in the area, a BBC Verify investigation revealed last month.

In Gaza City’s Zeitoun neighbourhood images show what appear to be four clusters of IDF armoured vehicles. In a 24-hour period between 1 and 2 September, dozens of buildings which had stood in an area between the vehicles have been demolished.

By 4 September the armoured vehicles had moved on, images reviewed by BBC Verify showed, with further damage inflicted on buildings in the area.

Elsewhere in Zeitoun, rows of tents set up by displaced Palestinians have disappeared in little over a month. According to the UN, more than 1.9 million Gazans – about 90% of the population – have been displaced by the Israeli military campaign.

According to the UN, hundreds of thousands of people displaced by fighting had returned to northern Gaza earlier this year after the Israeli military opened a corridor from the south of the strip during the short-lived ceasefire agreement.

High-rise buildings which had surrounded the tents have also been destroyed, while signs of activity on the streets have also disappeared. Fresh track marks left by IDF vehicles passing through areas where buildings once stood are also visible.

Similarly, in the Tuffah neighbourhood – where Israeli strikes killed at least eight people on Thursday, according to the Hamas-run Civil Defence agency – more buildings have been levelled.

On 1 August IDF armoured vehicles were visible in the area. By 1 September buildings near where the vehicles were active had been destroyed, including a school.

The images also appear to show fresh tracks left by armoured vehicles crossing through a cemetery, where over 3,000 troops killed fighting for the British Empire in World War 1 are buried. The cemetery has already been heavily damaged by bombardments earlier in the conflict, with a crater left by a previous strike also visible.

An IDF spokesperson told BBC Verify, without providing evidence, that: “In certain cases, entire neighbourhoods in the Gaza Strip are converted into combat complexes which are utilized for ambushes, housing command and control centres and weapon warehouses, combat tunnels, observation posts, firing positions, booby-trapped houses, and for setting explosives in the streets.”

Last month, Hamas said it had accepted a plan from regional mediators Qatar and Egypt that would see 10 living hostages and the bodies of 18 dead hostages released during a 60-day truce in exchange for hundreds of Palestinian prisoners and detainees in Israeli jails.

Israel has not responded to the plan but insists all the hostages must be released in one go.

Israel launched a military campaign in Gaza in response to the Hamas-led 7 October attack, in which 1,200 people were killed and 251 more were taken hostage.

At least 64,231 people have been killed in Israeli attacks in Gaza since then, according to the territory’s Hamas-run health ministry.

Additional reporting by Paul Brown and Merlyn Thomas.

Thousands of reservists have begun reporting for duty as the Israeli military presses ahead with its offensive to conquer Gaza City.

Ground forces are already pushing into the outskirts of Gaza’s largest urban area, which the military has said is a stronghold of Hamas.

The city is also coming under heavy Israeli aerial and artillery bombardment, with local hospitals saying that more than 50 Palestinians have been killed there since midnight.

The military has ordered residents to evacuate and head south immediately. The UN says an estimated 20,000 have done so over the past two weeks, but almost a million remain.

UN humanitarian officials have warned that the impact of a full-blown offensive would be “beyond catastrophic”, not only for those in the city but for the entire Gaza Strip.

Last month, the Israel Defense Forces (IDF) said about 60,000 reservists would be called up ahead of “Operation Gideon’s Chariots II” – the next phase of the ground offensive that it launched in May and has seen it take control of at least 75% of Gaza.

It also extended the service of 20,000 reservists who had already been mobilised.

On Tuesday, an Israeli military official said thousands had begun reporting for duty.

Israeli media said many of the reservists would be deployed to the occupied West Bank and northern Israel to free up active-duty personnel for the offensive.

They also reported that some combat units were seeing lower turnout than for previous call-ups, with reservists who had already served several tours during the 22-month war requesting exemptions for personal or financial reasons.

Prime Minister Benjamin Netanyahu announced that Israel would conquer all of Gaza after indirect talks with Hamas on a ceasefire and hostage release deal broke down in July.

At a government meeting on Sunday, he said the security cabinet had agreed the IDF’s objectives were “defeating Hamas and releasing all of our hostages”.

The armed group is currently holding 48 hostages, 20 of whom are believed to be alive.

The hostages’ families fear the new offensive will endanger them and are demanding the prime minister negotiate an agreement that would secure their release.

“Stop the war and bring all the hostages home in a deal – the living and the dead alike – some for rehabilitation in their families’ embrace, others for proper burial on Israeli soil,” said the daughter of Ilan Weiss, one of the two hostages whose bodies were recovered by Israeli troops in Gaza last week, at his funeral in Kibbutz Be’eri on Monday.

The IDF’s Chief of Staff, Lt Gen Eyal Zamir, has urged Netanyahu to accept a current proposal from regional mediators that would see about half of them released during a 60-day truce. However, the prime minister has said Israel will only accept a comprehensive deal that would see all the hostages freed and Hamas disarmed.

There were reportedly angry exchanges between Zamir and ministers at a meeting on Sunday.

The general warned that their Gaza City plan would put the hostages at risk and lead to Israel establishing a military government there, according to Israeli media. One unnamed senior minister was quoted by the Ynet website as saying that the general “did everything to convince against the plan, but made it clear several times that he would carry it out”.

In an address to reservists at Nachshonim base in central Israel on Tuesday, Zamir declared that the IDF was preparing for nothing less than “decisive victory”.

“We are going to increase and enhance the strikes of our operation, and that is why we called you,” he said. “We will not stop the war until we defeat this enemy.”

On the ground in Gaza on Tuesday, hospital officials said Israeli strikes and fire had killed at least 95 Palestinians since midnight.

Al-Shifa hospital in Gaza City reported 35 of the deaths, including nine people who were killed in an air strike in the southern Tal al-Hawa neighbourhood and seven others killed in a strike on a house in the northern neighbourhood of Sheikh Radwan.

The UN has warned that forcing hundreds of thousands of people to move further south is “a recipe for further disaster and could amount to forcible transfer”, which would be a war crime.

Global food security experts have confirmed that a famine is occurring in Gaza City and projected that it will expand to the central city of Deir al-Balah and the southern city of Khan Younis by the end of September.

The UN has also said tent camps for the displaced in the south are overcrowded and unsafe, and that southern hospitals are operating at several times their capacity.

In Khan Younis on Tuesday, Nasser hospital said it had received the bodies of 31 people killed by Israeli fire, including 13 who died in two strikes in al-Mawasi and Khan Younis camp.

Medics in the hospital’s emergency department told the BBC that most of the casualties being treated were children and elderly.

“We can’t deal with any more cases due to high pressure on us and lack of supplies. The CT [scanner] is now broken down, so we are working blindly,” one doctor said. “The current situation is catastrophic.”

Gaza’s Hamas-run health ministry meanwhile said that 13 Palestinians, including three children, had died as a result of malnutrition across the territory over the past 24 hours. That increased the total reported during the war to 361, including 185 in August alone, it added.

The UN has said the famine is a “man-made disaster” and said Israel is obliged under international humanitarian law to ensure food and medical supplies for Gaza’s population.

Israel has said there are no restrictions on aid deliveries and has disputed the health ministry’s figures on malnutrition-related deaths.

The Israeli military launched a campaign in Gaza in response to the Hamas-led attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

At least 63,633 people have been killed in Gaza since then, according to the territory’s health ministry.

Planes and tanks have pounded parts of Gaza City as Israel’s plans to seize the territory’s largest urban area increase pressure on nearly a million Palestinians living there.

Residents have spoken of uninterrupted explosions in northern and eastern parts of the city.

Israeli troops have also returned to blow up buildings in the refugee camp of Jabalia further north.

Sixty-four people were killed and nearly 300 injured in Israeli attacks in the past 24 hours, the territory’s Hamas-run health ministry said.

It said the overall number of those killed since Israel launched its massive campaign to defeat Hamas had risen to 62,686 – with another 157,951 injured.

Israel’s military launched an operation in Gaza in response to the Hamas-led attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

Israel’s Prime Minister Benjamin Netanyahu has vowed to defeat Hamas and defied international criticism over his plans to expand the war.

Some 60,000 reservists are being called up to take part in the Israeli operation.

While it has yet to begin in earnest, Israeli attacks on Gaza City have continued unabated – with the areas of Zeitoun and Shejayia hit from the air overnight into Sunday, as tank fire targeted Sabra neighbourhood.

The Israel Defence Forces (IDF) have also said that troops have returned to the Jabalia area in the past few days.

“The troops’ activity enables the expansion of the fighting to additional areas and prevents Hamas terrorists from returning and operating in these areas,” the IDF said.

Separately, the World Health Organization (WHO) announced on Sunday that a staff member had been released by the IDF after being held in Gaza since 21 July. There are no further details about the identity of the WHO worker or the reasons for his detention.

Netanyahu is also facing intense pressure in Israel – particularly from the families of hostages who want him to negotiate an end to the war in order to bring their captive relatives home.

Only 20 of 50 hostages still held in Gaza are believed to be alive.

The Israeli prime minister announced Israel’s intention to conquer the entire Gaza Strip after indirect talks with Hamas on a ceasefire and hostage release deal broke down last month.

Mediators Qatar and Egypt are trying to secure a deal to avert the offensive and have presented a new proposal for a 60-day truce and the release of around half of the 50 hostages, which Hamas said it had accepted.

But Israeli officials have said they will no longer accept a partial deal and have demanded a comprehensive one that would see all the hostages released.

Israel’s defence minister warned that Gaza City will be razed if Hamas does not agree to disarm and release all hostages.

The Israeli military has said it plans to evacuate Gaza City’s entire population and move it to shelters in the south before troops move in.

Most of Gaza’s population has been displaced many times.

The UN and non-governmental organisations have warned that an Israeli offensive in Gaza City will have a “horrific humanitarian impact”.

More than 90% of homes are estimated to be damaged or destroyed, and the healthcare, water, sanitation and hygiene systems have collapsed.

Eighteen of Gaza’s 36 hospitals are currently partially functional, according to the UN – 11 in Gaza City and its surrounding areas and one in a separate administrative district in North Gaza.

On Friday, conditions of famine were confirmed in Gaza City and its surrounding areas for the first time.