Mary Yusuf Sharmin, 18, committed suicide on Monday afternoon at her house in Sutkhalpur area of Dhalpur in Demra.

A member of her family said she had returned from local hoodlum Mohammad Ali alias Raju's residence just half an hour ago. She went there to negotiate the release of her brother who had been taken captive by Raju's gang the previous day.

Police in the afternoon recovered the body hanging from the ceiling and sent it to Mitford hospital for autopsy.

Earlier on Sunday night, Raju, along with his younger brother and an associate, broke into Mary's house and kidnapped her younger brother Shahin. They also assaulted her mother Nazma Begum, the family source said.

On Monday morning, Raju with two accomplices came to Mary's house and asked her to go to his house. He warned Mary and her family that if she did not go to his house, he would kill them all, including her brother.

Anxious for family members' safety, Mary went to Raju's house and stayed for about an hour. On return from there she locked her in a room and committed suicide.

Mary's father Yusuf Ali, who hailed from Gafargaon of Mymensingh, filed a murder case with Demra Police Station the same day accusing Raju of being the cause for her to suicide.

Neighbours suspect that Mary's family left the house for fear of reprisal.

Mary's family members said Raju, the wayward son of Sarafat Ali, had been teasing her for more than two years. And at one stage she had to stop her studies due to his incessant harassment. She was not safe even in her house as he often went to her house to force her to have an affair with him.

"Raju made a marriage proposal lately but we flatly refused," said Yusuf in the FIR (first information report).

Demra police could not yet nab anyone till yesterday evening.

Bangladesh Mohila Parishad in a press release demanded arrest and punishment of the culprits.