TEHRAN — Iran said Tuesday it believes the remaining workers trapped by an explosion at a coal mine in the country’s east have died, bringing the death toll in one of its worst industrial disasters to at least 49.

A provincial emergency official, Mohammad Ali Akhoundi, gave the death toll in a report carried by Iranian state television from the mine in Tabas.

Figures for the numbers of miners inside the mine at the time have fluctuated since a methane gas leak Saturday sparked an explosion at the coal mine in Tabas, about 540 kilometers (335 miles) southeast of the capital, Tehran.

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Deadly Gas Leak and Explosion

Around 70 people had been working at the time of the blast. Bodies recovered so far showed no signs of blast injuries, suggesting many of the workers died from the gas before the blast.

Such gases are common in mining, though modern safety measures call for ventilation and other measures to protect workers.

It wasn’t immediately clear what safety procedures were in place at the privately owned Tabas Parvadeh 5 mine, operated by Mandanjoo Co. The firm could not be reached for comment.

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Safety Concerns Raised

On Tuesday, a lawmaker and member of parliament’s mine committee said the safety system of the mine was not working and “even the central alarm system was broke or did not exist.”

Lawmaker Zahra Saeedi added that workers learned of the safety issue just before the disaster but couldn’t leave in time. Two of the dead were health and safety experts at the mine, she said.

Iran’s new reformist president, Masoud Pezeshkian, in New York for the U.N. General Assembly, has said he ordered all efforts be made to rescue those trapped and aid their families. He also said an investigation into the explosion was underway.

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History of Mining Disasters in Iran

Iran’s mining industry has been struck by disasters before. In 2017, a coal mine explosion killed at least 42 people. Then-President Hassan Rouhani, campaigning ahead of winning reelection, visited the site in Iran’s northern Golestan province and angry miners besieged the SUV he rode in, kicking and beating the armored vehicle in a rage.

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 were often blamed for the fatalities.