Around 1.30 a.m. I received a call from his wife that Singh had not reached home. I told her that he would reach soon. Around 2.30 a.m. I received a call from Delhi Police that he had been murdered,' Himanshu told reporters.

'I haven't seen his body but police told me that his body has five to seven stab wounds. Police have told me that Singh was stabbed somewhere else and his body was shifted to the spot later,' he said.

There were reports that he had named members of the Akhil Bharatiya Vidyarthi Parishad (ABVP) - the students wing of the Bharatiya Janata Party (BJP) - as being behind the murder.

Denying the allegation, ABVP vice-president Vikas Dahiya said: 'If he is alleging that the ABVP is behind the incident, it is ridiculous.'

A court in Maharashtra had on July 13 acquitted six students accused of beating to death Prof Sabharwal in Ujjain's Madhav College in August 2006.

The six accused, said to be activists of the ABVP, were let off due to lack of evidence against them.