New Delhi, Jan 03 (Agencies): Investigators were on Monday groping in the dark in linking the chain of events that led to the murder of a teenaged girl who had left her home on the New Year eve with some "known" person.

The 17-year-old girl had left her home on December 31 evening but was found murdered in a vacant plot owned by Delhi Metro in Dwarka Sector 14 on Saturday.

Police is yet to link the missing gaps in the case as they are yet to establish what led to the murder of the girl who, according to them, appeared to have "consensual sex".

"Our investigations have shown that she was not going for any New Year party. A family which shares their rented house with the victim's brother had told us that she had gone out in a casual manner.

"It did not suggest that she had gone for a party. Also, she used to go out regularly and come back home as late as one am. This was why the brother was not unduly worried about her that day," Sharad Aggarwal, Deputy Commissioner of Police (South-West), said.

He also said that she did not have food in the night as the post-mortem had shown that she had an empty stomach.

Asked whether she was gangraped, he said only a detailed forensic examination of vaginal swab could say that.

"There was definitely sexual intercourse before she was murdered. But we cannot say that she was raped as of now. Doctors say there were no injury marks on her private parts," he said adding that reports of she being gangraped were "pure imagination".

He said somebody known to her taken her out. "We have no clue of what happened or what led to the murder," he said.

"She was first strangled with her own denim trousers which was found wrapped around her neck. Then her face was smashed with stones to make the identification of the victim difficult," he said.

This is the first case of crime against woman reported in the capital this year.

The victim, whose parents have died, was residing with her brother in the servants' quarters of Lady Hardinge Hospital.