Security officers of Alipore Central jail found gangster Gopal Tiwari strutting around in his cell, cellphone to his ear, during a surprise raid on Tuesday afternoon.

“We were stunned but Tiwari seemed unperturbed, as if nothing had happened,” said one of the officers.

A search of the cell revealed seven more mobile phones loaded with prepaid SIM cards that had been activated recently.

Tiwari and two others had been hired by Haldiram’s owner Prabhu Shankar Agarwal to kill a trader. All four were awarded life term on January 29 and are lodged in the same ward of the jail.

Preliminary investigation by the jail authorities revealed that Tiwari kept in touch with his gang members using five of the seized cellphones. “We are yet to establish who used to operate the other three cellphones,” said an officer.

Aftab Ansari, the mastermind of the American Center attack and the abduction of a Khadim’s co-owner, is also lodged in Alipore Central jail. His aides are suspected to be behind the pay-up-or-face-abduction threat calls to four city businessmen a week ago that had sparked panic.

A SIM card was found on another prisoner of the jail last week.

A jail officer said a fresh charge of violating jail norms would be slapped on Tiwari.