Face of man wanted in connection with murder of students

Police released an e-fit image last night of a man they are hunting in connection with the brutal murder of two French students in a south-east London bedsit.

The black and white image is a computer-generated impression of a white male seen running from the scene eight days ago, at about the time neighbours reported hearing an explosion. He has been described as between 30 and 40, of slight/slim build and wearing a light coloured baseball cap and a dark top, blue jeans and white trainers.

Police later discovered the bodies of 23-year-old bio-engineering students Laurent Bonomo and Gabriel Ferez, who had been tied up and stabbed up to 250 times before being set on fire.

The e-fit was distributed by detectives three hours after they released a 21-year-old man without charge. He was arrested at 3.40am on Saturday and is the only person to be detained in connection with the case.

Officers returned to the scene of the crime in New Cross last night to appeal for help in tracing the killer. They were hoping that by revisiting the area close to Sterling Gardens, they would be able to speak to people in the vicinity at the same time the previous Sunday, when the students were murdered.

Gabriel Ferez's parents released a statement urging the killer to hand himself in. "You will not be able to live in hiding for ever," they said. "You may be scared and feel like a coward, but you must recognise this terrible mistake you made."

M. Bonomo and M. Ferez, who were on a three-month placement at Imperial College, were killed sometime on Sunday 29 June as they played a computer game in M. Bonomo's flat.

One theory that police are investigating is the possibility that they were killed by a burglar. A laptop was stolen from the flat the previous weekend and one line of inquiry is that the thief returned. There was no sign of forced entry before the murder.

Tonight a silent march will take place in memory of the students in Clermont-Ferrand, the town in central France where they studied before coming to England on placement. It has been organised by the university's student federation. M. Bonomo was its president until February.

Amid increasing political pressure to tackle knife crime, the Home Secretary, Jacqui Smith, is reported to be considering the introduction of a requirement for doctors to notify stabbing injuries to the authorities, in the same way as gunshot wounds, to allow police to gather information about incidents that might go unreported.

Tony McNulty, the Policing minister, warned yesterday that carrying knives was getting into teenagers' "collective DNA".

A man in his twenties was attacked with a knife in Putney Heath, south London at around 5am yesterday. On Saturday a 25-year-old man was stabbed in the mouth in an unprovoked attack in Southend, Essex, and three men and a teenager were attacked with knives in Salford, Greater Manchester. Graham Mitchell, 39, of Walker, Newcastle, will appear before magistrates tomorrow charged with the attempted murder of a 25-year-old woman and a 26-year-old man, who were stabbed in Newcastle on Saturday. A man was stabbed at a working men's club in Sunderland on Saturday and a 19-year-old man was knifed in Merseyside on Friday night.

The glut of stabbings has prompted the police to name knife crime their number one priority – ahead of terrorism – and the NHS to order stabproof vests for frontline workers.