Aman Singh, one of the prime suspects in the murders of Durgapur-based coal trader and BJP leader Raju Jha and hotelier Arvind Bhakat of Asansol, was shot dead in a Jharkhand jail reportedly by one of the inmates on Sunday night.

A police officer in Dhanbad where Aman was lodged said he had died on the spot after being hit by three bullets in the chest. Aman was declared dead at the jail hospital. Doctors found three bullets lodged in his chest.

The police officer said that based on CCTV footage, the assailant was identified and arrested.

Aman was also reportedly involved in the murder of former deputy mayor of Dhanbad Niraj Singh.

He was earlier lodged in Hazaribagh jail but was shifted to the Dhanbad correctional home after investigators found his involvement in the murder of the deputy mayor.

The murder of Aman in judicial custody has raised questions about the Dhanbad jail’s security system. Senior police and administrative officials in Dhanbad rushed to the spot after the incident and ordered a probe.

“We have already identified the person who fired at Aman Singh. We have also formed a committee to probe the incident,” said Varun Ranjan, deputy commissioner and district magistrate of Dhanbad.

The police have filed a suo-motu case against the assailant.

Sources said the man who fired at Aman is a theft accused and was brought to the jail recently.

“It is not yet clear from where he got the firearm or who had supplied it to him. We will interrogate him to know why he killed Aman. The person is accused of theft. We are also probing whether this man had deliberately committed the theft to get access to the jail to kill Aman,” said a senior police officer in Dhanbad.

East Burdwan police got Aman’s name while investigating Jha’s murder. The investigators also interrogated Aman twice in Dhanbad jail and got the names of two persons. They were later arrested from Ranchi and Gaya.

Kundan Singh, another professional killer arrested in a jewellery shop heist in Nadia’s Ranaghat in August, told the police that he used to work for Aman and had held meetings with him in jail before murdering Jha.

Jha was shot dead by three assailants — one of them was Kundan — at Shaktigarh in East Burdwan on April 1. Jha, along with prime accused in cattle smuggling case Abdul Latif, were going to Calcutta in an SUV when the murder took place when they had stopped at Shaktigarh.

The police probing the murder of hotelier Arvind Bhakat of Asansol also interrogated Aman in jail after they suspected his involvement in the crime.

Bhakat was shot dead in his hotel in Asansol on February 17. Investigators of both the murders found a common link — Aman Singh. The police said Aman’s murder in jail might have links with the murders in Asansol and Shaktigarh.