A massive explosion ripped a boiler on Wednesday afternoon at the state-run NTPC's Unchahar plant in UP's Rae Bareli district.

"This is to inform that Unit 6 (500 MW) of Feroze Gandhi Unchahar Thermal Power Station, Raebareli, U.P., is under shutdown after an accident in the evening of 01.11.2017. The other five units of the station are operating normally," NTPC said in a statement on Thursday morning.

Chief Minister Yogi Adityanath expressed his condolences over the deaths and announced ex-gratia of Rs 2 lakh for next of kin of deceased and Rs 50,000 for the grievously injured, an official said.

A team of 36 National Disaster Response Force (NDRF) personnel are at the spot to speed up the rescue work.

The 1,550-MW plant supplies electricity to nine states, according to officials, and employs around 870 people.

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