A murder case has been started against the three boys who had suppressed the news of 16-year-old Arijit Ghosh’s drowning in the Hooghly on Saturday morning.

The boys had gone to Babughat for an early morning dip. Arijit was the trio’s classmate till last year.

“Based on a complaint by Arijit’s parents, we have started a case under Section 302 of the Indian Penal Code. We are trying to ascertain the veracity of the complaint,” said an officer of South Port police.

The boys were interrogated for several hours at Muchipara police station on Tuesday night, before it was decided that a murder case would be started. Officers from the homicide wing of the detective department were present during the grilling.

According to Arijit’s family members, the trio had called him to Babughat on Saturday. The boy, who was staying with his grandmother in Serpentine Lane, took Rs 1,500 from her to pay an electricity bill.

The three returned without Arijit and confessed only on Sunday evening that the boy had drowned.