The fire reportedly started at 10:30 PM on Thursday.
Rescue officials have retrieved bodies of nine people who were trapped inside a hydroelectric plant in Telangana which had caught fire late last night. They were missing following the fire at unit one of the under tunnel power house of the Srisailam hydroelectric plant, which is near Telangana's border with Andhra Pradesh.
"Two of the bodies are of Assistant Engineers," Nagarkurnool Collector L Sharma was quoted as saying by news agency PTI.
Thick smoke is still coming out of the tunnel where the hydel project is located and efforts are on to lessen its intensity, he said.
CISF personnel have also joined the rescue operations which is being led by the National Disaster Response Force (NDRF). Teams from Singareni with experience in handling underground units are also present at the accident site.
Telangana Chief Minister K Chandrasekhar Rao has ordered a CID probe into the accident.
Andhra Pradesh Chief Minister YS Jagan Mohan Reddy has ordered the officials to extend all possible help to Telangana counterparts for the rescue operations. Mr Reddy has also cancelled his visit to Srisailam which was scheduled for today in the wake of the accident.
Prime Minister Narendra Modi tweeted about the fire and prayed for the early recovery of those injured: "Fire at the Srisailam hydroelectric plant is deeply unfortunate. My thoughts are with the bereaved families. I hope those injured recover at the earliest."
Vice-President M Venkaiah Naidu also expressed grief over the loss of lives in the fire at the Srisailam hydroelectric plant in Telangana.
"Distressed by the loss of lives in a fire incident at Srisailam hydroelectric plant in Telangana. My thoughts are with the bereaved families," Mr Naidu said in a tweet.
Twenty people were on shift when the fire started around 10.30 PM on Thursday. While 11 people managed to escape, nine others, including a division engineer, four assistant engineers, two junior plant attendants and two others from Amara Raja Batteries were trapped inside.
"As soon as the fire started, they tried to trip the units but that couldn't happen. So we isolated the 400 KV input and all units were tripped," Telangana Transco CMD D. Prabhakar Rao said.
According to initial reports, a short circuit at the underground hydroelectric power station situated at Srisailam dam's left bank is suspected to have led to the fire.
"The project unit operates at multiple levels. Those in the control room are said to have managed to come out. Others at lower levels couldn't come out because of the smoke. The current being switched off also hampered rescue and escape efforts," said one official.
Energy minister Jagadish Reddy, minister Niranjan Reddy, CMD Prabhakar Rao, who reached the accident site at the night, are overseeing rescue efforts.
This is the first such accident at the plant, said Mr Rao. "Why it happened has to be investigated. How much damage has happened we will know only after the smoke goes away. Our priority right now is to rescue those trapped inside," he added.
With inputs from PTI