Reuters, 3 May 2017 – An explosion in a coal mine in northern Iran on Wednesday killed at least 21 workers and injured scores, state media reported.

The blast occurred at 12:45 p.m. local time (0745 GMT) in the Zemestanyurt mine when workers tried to jump-start a locomotive.

“Twenty-one bodies of workers …have been taken out of the mine …So far there have been 69 injured,” a regional official in Golestan province said.

Iranian media said more than 30 of the injured were transferred to nearby hospitals.

A man reacts near the site of an explosion in a coal mine in Golestan Province, in northern Iran.

The semi-official Fars news agency reported earlier that more than 50 workers were trapped in a two-kilometre-long tunnel filled with gas that hampered rescue efforts.

The mine has 500 workers and the explosion happened during a change of shift, Fars reported.

Iran extracted 1.68 million tons of coal in 2016, an increase on previous years. It uses most in domestic steel production and exports only a fraction.