Altogether 24 people were injured, four seriously, in a fire at SAIL's IISCO steel plant in West Bengal on Thursday, police said.
All the 24 people were admitted to the hospital, the police said.
"We are investigating the reason behind the fire. Out of these 24 people, three are CISF employees. The company officials are also looking into the reason behind the fire," Abhijit Chatterjee, officer-in-charge of Hirapur police station, under which IISCO falls, told PTI.
Watch:Mishap in SAIL's Bengal plant
Burdwan district magistrate Soumitro Mohan said 20-23 suffered burns and four of them were in serious condition in the hospital.
Efforts are on to transfer the seriously injured to a private hospital in Durgapur and the SDO, Asansol, has been sent to Burnpur, he added.
State-owned SAIL had said earlier in the day that 21 people were injured in the blaze and two of them were in the hospital ICU.
"An incident of fire occurred at SAIL's IISCO Steel Plant (ISP) at 12.15 PM today... Around 21 affected persons have been provided immediate medical attention, both at the plant medical unit and at Burnpur hospital. Out of these, two persons belonging to contractor BEC have been admitted to ICU," SAIL said in a statement.
Preliminary inquiry revealed that it happened in New Coke Oven Battery number 11, it said adding the fire was immediately extinguished.
The incident occurred during a planned shutdown for carrying out rectification jobs in one of the pre-heaters of the coke oven battery, the statement added.