A 13-year-old help who was rescued from a burning flat near Jodhpur Park told police on Monday that three unknown youths had locked him in a room and set it on fire.

This was the first time since the October 20 incident that the police could speak to Sunil Ray, who suffered burns and has not recovered yet.

“Sunil told us that the three youths, who were speaking in Bengali, entered the flat and dragged him into a room. They threatened to kill him if he raised an alarm. After a couple of minutes, they tied his hands and legs with a rope and set the room on fire after locking it from outside,” said an officer of Lake police station. “We have launched a search for the three youths.”

According to the help’s statement, the family members had gone out to meet someone from the locality when the trio entered the Gobindopur Road flat. “We are trying to ascertain whether the family members had any link with the three youths,” the officer said.

All four members of the family — Bhupinder Singh Dhingra and Ravindra Singh Kaur, and their two sons, Harmit and Kulbhusan — were arrested on the attempt to murder charge a day after the incident. They were produced in Alipore court on Monday and granted interim bail.

The police said Sunil, who is from Bihar, is still traumatised.

“He is yet to get over the shock and was shuddering with fear while recalling the incident,” said an officer.

Sunil was employed by the family two weeks before the October 20 fire.

Sleuths have recorded the statements of some neighbours who alleged that the family members used to torture the boy.