A 19-year-old youth committed suicide at his Barasat home, reportedly after failing to persuade his friends not to humiliate a girl.

Residents of Aswinipalli said they saw Biswajit Roy leave the house where the girl was being humiliated on Sunday night, “his head hung in shame”. Moments later, he hanged himself.

The residents handed over four youths to police. The girl and another member of the group, Amrit, are missing.

The police have come to know during interrogation that Mohammad Sariful, 21, had come to friend Subhash Mandal’s house with his girlfriend. Apart from Mandal, there were four others in the house then — Biswajit, Amrit, Raja and Santu.

Soon after, Mandal and four others left to buy liquor, leaving Sariful and the girl in the house. They returned after half an hour and started drinking. The couple were in another room and did not join them.

A few minutes later, an altercation broke out between Sariful and his friends. Neighbours heard Mandal, Amrit, Raja and Santu asking Sariful for money. “They threatened the youth that unless he paid up, they would spread the word that he had spent a few hours with the girl in a closed room. But Sariful refused to bow to the pressure,” said Peejush Roy, a neighbour of Mandal.

The gang then dragged the girl out of the room and locked in Sariful. By this time, hearing the commotion, several people had gathered in front of the house.

“We saw Biswajit protesting his friends’ attempt to blackmail Sariful. On seeing us, one of the youths asked the girl to leave the house immediately, or else she would be in the eye of a scandal,” said Prabir Sarkar, another local resident.

The youth, later identified as Amrit, “forced” the girl to ride pillion on his two-wheeler. The neighbours then intervened, herding the youths into the house before calling the police. “Biswajit by then had left the spot, hanging his head in shame. A couple of hours later, we came to know that he killed himself,” said Sarkar.

Amrit and the girl are yet to be traced, though the two-wheeler has been found lying on the road.

A Barasat police station officer said: “A few youths were involved in criminal activities in the house. There was a woman in the group. It is not clear if Biswajit’s suicide is linked to the trouble in the house.”