A college student was arrested on Friday on the charge of making prank calls to police warning about blasts in the city.

Anirban Sanyal, 22, a third-year undergraduate student majoring in political science at St. Paul's College, was picked up from his house on Kakulia Road near Ballygunge. The police zeroed in on Anirban after the calls were traced to his cell phone number.

The police said Anirban made the first call at 5.30pm to Lake police station, identifying himself as Dawood Ibrahim. He hung up after the cop who answered the call started questioning him.

Three minutes later he called Lalbazar, saying in Hindi: " Kalkatta mein dhamaka hoga (There will be blasts in Calcutta)."

An officer said the two calls were traced to the same cell phone number. "We got the caller's address from the mobile service provider and picked him up from his home on Kakulia Road, under Gariahat police station," the officer said.

Anirban was taken to Gariahat police station, where he allegedly admitted to making the prank calls. "We decided to arrest him because we wanted to set an example and spread the message that making such calls was a serious crime," the officer said.

Officers said they dealt with the case seriously because of the recent spate of blasts triggered by terrorists in Bangladesh and other countries.