Pradip Bose, the mastermind of the city police constabulary recruitment scam, surrendered in Bankshall court on Friday and was remanded in judicial custody, limiting the scope for interrogation.

The former constable entered the court of chief metropolitan magistrate S.S. Anand around 10am with seven lawyers in tow.

The detective department had been looking for Bose, alias Bappa, who would arrange for dummy candidates to represent his clients in tests for recruitment to the constabulary, for over two months.

The police teams raided his possible hideouts in Arambagh, Burdwan and other locations in North 24-Parganas, but he evaded arrest.

“We tried to monitor calls made from his cellphone, but he kept changing the SIM and the handset frequently,” an officer said.

Bappa is the 18th scam accused to be in either police or judicial custody. The list includes four policemen.

One of Bappa’s accomplices, Santosh Jadav, was arrested a couple of days ago and remanded in police custody by the same magistrate.

“We had conducted a massive operation to track down Bappa. He is the person who started the racket two years ago and collected several lakhs from candidates for jobs in the force,” said Jawed Shamim, the deputy commissioner of the detective department.

Another officer said Bappa being sent to jail instead of the police lock-up was a jolt to the probe.

“We wanted to interrogate him. He is the only person who can only tell us to what extent his business had spread.”

A judicial remand means the police will now have to seek the court’s permission to interrogate him, even for a limited period.

Bappa had joined the police force in 1997 and was dismissed from service two years ago for not reporting for duty.