Citing the head of Iran’s Red Crescent, state TV said earlier on Sunday that 24 people were missing.
According to Reuters news agency, Iranian President Masoud Pezeshkian expressed condolences to the victims’ families.
“I spoke with ministers and we will do our best to follow up,” Pezeshkian said in televised comments.
The Tabas mine covers an area of more than 30,000 square kilometres (nearly 11,600 square miles) and holds mass reserves of coking and thermal coal, according to IRNA.
It is “considered the richest and largest coal area in Iran,” IRNA said.
Local prosecutor Ali Nesaei was quoted by state media as saying “gas accumulation in the mine” has made search operations difficult.
“Currently, the priority is to provide aid to the injured and pull people from under the rubble,” Nesaei said.
He added that “the negligence and fault of the relevant agents will be dealt with” at a later date.
Last year, an explosion at a coal mine in the northern city of Damghan killed six people, also likely the result of methane leak according to local media.
In May 2021, two miners died in a collapse at the same site, local media reported at the time.
A blast in 2017 killed 43 miners in Azad Shahr city in northern Iran, triggering anger towards Iranian authorities.
