The CBI team probing the killing of DSP Zia-ul-Haq on Sunday detained a person said to be close to former UP minister Raghuraj Pratap Singh ‘Raja Bhaiya’, who is also among the accused in the case.

Chavinath Yadav is suspected to be involved in illegal sand quarrying in Maudwara and Betni villages of the district and the slain official had been running a drive against the racket there, the CBI sources said.

Mr. Chavinath along with Gulshan Yadav, who is also an accused in Haq’s murder and is on the run, are allegedly part of the quarrying racket and both are said to be close to Raja Bhaiya, CBI sources said.

The CBI has booked five persons in the case. While two of the accused -- Sanjiv Pratap Singh alias Guddu Singh and Rajeev Pratap Singh -- are under CBI custody, the other two Gulshan and one Hari Om Shrivastava are absconding.

Raja Bhaiya is the fifth accused in the case.

Meanwhile, the CBI team visited Manikpur and Sangrampur villages with relatives of slain village head Nanhe Yadav along with Kamta Pal, the accused in Nanhe’s murder.

As part of its investigation, the team also went to the site where Nanhe’s brother Suresh Yadav was killed, sources here said.

Earlier in a major breakthrough on Saturday, the police had claimed to have recovered the service revolver of slain Kunda officer.

Haq was shot dead by an enraged mob when he had rushed to control the volatile situation after a village head was shot dead following a land dispute.

With his name cropping up in the matter, Raja Bhaiya had resigned from the UP cabinet on March 4.

The Uttar Pradesh government had recommended a CBI probe into Haq’s murder and the Central agency had taken over the investigations on March 7.