Iranian search crews have found seven more bodies at the site of last week's coal mine explosion in northern Golestan province, raising the number of confirmed fatalities in the incident to 42, state TV reported on Tuesday.
The explosion last Wednesday at Zemestanyurt mine has been blamed on methane gas that had accumulated in the mine. The incident is believed to be the worst industrial accident to strike Iran in the last few decades.
Earlier, the death toll stood at 35.
Tuesday's report quoted Reza Morovati, an official in the Golestan government, as saying that the seven more bodies that were found were taken to "forensics experts for identification." He also said it was possible that up to two miners remain trapped inside the coal mine.
Iranian media have reported that at least 75 were injured in the explosion, and that the methane gas also sickening dozens who later rushed into the mine to try to rescue those trapped. Most of the injured have been discharged from hospitals.
On Sunday, angry coal miners and relatives of those killed or injured in the explosion kicked and beat a car carrying Iranian President Hassan Rouhani as he tried to leave after visiting the Zemestanyourt mine. Rouhani was unharmed and eventually left the site.
The president earlier spoke to a gathering of the miners and acknowledged that the government was "responsible for their lives." His stop in Golestan came during his campaign tour — Rouhani is running for another four-year term as Iran's elected president in the May 19 presidential election.
"Be sure that we will pursue this issue and also your demands," Rouhani told the miners. "Those who are guilty in this incident should be prosecuted by a court."
Rouhani remains the favorite in the election though there is much discontent in the country as benefits of a landmark nuclear deal with world powers struck by Rouhani's administration have yet to trickle down to the average Iranian.
More than 500 workers are employed at the Zemestanyurt mine in Golestan, which lies along Iran's northern border with Turkmenistan and also on the shore of the Caspian Sea.
Iran annually consumes some 2.5 tons of coal but only extracts about 1 million tons from its mines per year. The rest is imported, often consumed in the country's steel mills.
This is not the first disaster to strike Iran's mining industry. In 2013, 11 workers were killed in two separate mining incidents. In 2009, 20 workers were killed in several incidents. Lax safety standards and inadequate emergency services in mining areas are often blamed for the fatalities.
Since Iran's nuclear deal, the country has begun an effort to renovate some of its coal mines. Delegations have visited Tehran from foreign countries including the Czech Republic, hopeful for contracts.