Three people were rescued in an unconscious state from the fourth floor of Anusandhan Bhawan here after the building caught fire on Thursday evening, the official said.
The fire broke out at 7 p.m. on the fourth floor of Anusandhan Bhawan, which houses science and technology ministry, in the heart of the national capital.
At least 14 fire tenders were rushed to the spot and flames could only be doused after nearly two hours of firefighting.
"We have rescued three people who were lying unconscious inside the building. They have been admitted to the Ram Manohar Lohia Hospital," said an official of Delhi Fire Service.
The officials said the reason of the fire could not be ascertained immediately.