The four engineers injured in the blast were identified as Arvind Singh, Varun Gautam, Ashok Pal and Jayant Tiwari. They were rushed to a hospital where their condition is said to be stable.
The power generation in Anpara D, having installed capacity of 1,000 MW, came to a grinding halt following the blast and the resulting fire.
The thermal power station is owned by the Uttar Pradesh Thermal Power Generation Corporation.
The sudden outage of 1,000 MW power generation caused a power crisis in eastern Uttar Pradesh district.
Firetenders from Anpara A and B and Anpara C plants, run by the private Lanco Power, were rushed to the accident site. The fire was brought under control after nearly four hours.
Chief General Manager of Anpara D thermal power station, Heeraman Prasad Singh, said he was out of station and so was unable to comment.
He, however, said the blast and fire in the turbine generator was a huge loss and it could take more than six months to resume power generation.
Singh said a team of engineers was on the spot and they were investigating the possible cause of the explosion.