The toll in Wednesday evening’s explosion at a unit of thermal power firm NTPC – formerly known as the National Power Thermal Corporation – in Uttar Pradesh’s Unchahar town has now risen to 26, Principal Secretary (Home) Arvind Kumar told ANI. At least 66 people are believed to have been injured.

The number of casualties is likely to go up when the blades of the boiler plant are cut, the Uttar Pradesh Police said earlier. A team of the National Disaster Response Force is at the site. A magisterial inquiry will be conducted into how the explosion occurred, Rae Bareli District Magistrate Sanjay Kumar said.

Congress Vice President Rahul Gandhi met the injured and the families of the victims on Thursday morning. Party president Sonia Gandhi is the MP from the Rae Bareli Lok Sabha constituency.

Power Minister RK Singh said that a committee has been formed to find out what caused the blast and to decide precautionary measures for the future, according to ANI.

On Thursday, he also announced compensation of Rs 20 lakh to the families of the deceased, Rs 10 lakh for those who were seriously injured and Rs 2 lakh for those with minor injuries. This is “over and above the statutory compensation”, the Press Information Bureau said in a statement.

On Wednesday, Uttar Pradesh Chief Minister Adityanath had announced compensation of Rs 2 lakh for the families of those who died, Rs 50,000 for those critically injured and Rs 25,000 for the others injured. Prime Minister Narendra Modi had approved a compensation of Rs 2 lakh each for the families of the deceased and announced Rs 50,000 for each of those injured.

Uttar Pradesh Principal Secretary (Home) Arvind Kumar earlier said around 90 to 100 people were injured in the explosion. Some 22 victims with severe burn injuries were taken to a hospital in Lucknow for treatment. Several workers are feared trapped. Operations at the boiler plant has been closed.

In a statement, NTPC said that the unit burst with a “sudden abnormal sound” at 3.30 pm. Reports said a pipe exploded at the plant when hundreds of labourers were working inside.

Chief Medical Officer DK Singh confirmed the deaths. Chief Minister Adityanath ordered quick rescue and relief work. Prime Minister Narendra Modi said he was “deeply pained by the accident” and that “the situation is being closely monitored”.

The plant started generating power from coal in 1988.