The CBI on Wednesday took over the probe into the deaths of the three civil services aspirants at Rau’s IAS Study Circle in Delhi’s Old Rajinder Nagar and registered an FIR against the owner of the institute, sources said.

Shreya Yadav, 25, of Uttar Pradesh, Tanya Soni, 25, of Telangana and Nevin Dalvin, 24, of Kerala drowned on July 27 in the unauthorised basement library of the coaching centre after being trapped by flash floods. The move came after Delhi High Court directed the agency to take over the case from Delhi police. Sources said the CBI had registered a case against Abhishek Gupta, the institute owner.

“The CBI has booked Gupta for culpable homicide not amounting to murder, causing death by negligence, voluntarily causing hurt, negligent conduct and common intention,” said an agency official. The IAS aspirants were studying in the library set up in the basement when water flooded it, leading to their death.

Earlier, the high court had slammed the police and the Delhi Municipal Corporation over the deaths, saying it was unable to fathom how they could not come out of the basement. It sought to know whether the doors were blocked or the staircases narrow.

The court had also asked the central vigilance commission to nominate a senior officer to oversee the CBI probe into the criminal case.

The Aam Aadmi Party, which runs the civic body and the Delhi government, and the BJP, which has overarching powers in Delhi through the lieutenant governor, blamed each other for the mishap.

In the wake of the large-scale protests by civil service aspirants, the Delhi government has proposed a law to regulate coaching classes. The municipal corporation had also sealed the premises of 26 coaching centres and punished officials responsible for the clogged drains.