UPDATE 2 - 56 injured as powerful explosion rocks optical plant near Moscow

UPDATES WITH STATEMENT BY MOSCOW REGION GOVERNOR, CHANGES HEADLINE, DECK, LEDE

By Elena Teslova

MOSCOW (AA) – At least 56 people were injured on Wednesday after a powerful explosion occurred at a Russian optical plant outside the capital Moscow, authorities said.

"In total, 56 people applied for medical help. 30 are now in hospital, six of them are in intensive care. Another 26 people went to emergency rooms, they did not need hospitalization," Andrey Vorobyov, Moscow region’s governor, said on Telegram.

Almost 160 rescuers and law enforcement agencies are working on the spot in the city of Sergiyev Posad, 74 kilometers (45.9 miles) northeast of Moscow, and that rescuers will need about 12 hours to clear the rubble, he added.

"There may still be people left, three have already been removed – doctors assess their condition as serious ... The exact causes of the explosion remain to be determined," the mayor also said.

A total of 38 apartment buildings were affected by the blast, according to Vorobyov.

Earlier, a statement by Russia's Emergency Situations Ministry on Telegram said that 25 people were injured because of the explosion, and that more than 150 people are working at the scene, including search and rescue personnel and canine crews.

Russian state news agency TASS reported, citing sources in the emergency services, that the explosion occurred on the territory of the Zagorsk optical and mechanical plant.

“The explosion occurred on the territory of the Zagorsk optical and mechanical plant in the boiler room area. The blast wave knocked out windows in several houses in different parts of the city,” it said.

The plant's management announced evacuation of all buildings and workshops.

*Burc Eruygur contributed to this story from Istanbul.