Two police officers were injured by a suspected burglar wielding a knife last night. Both wore stab-proof vests but the knifeman aimed at their heads and faces.

One officer was slashed across the forehead but his woman colleague was protected from serious injury by her glasses - the 4in blade skimmed across the left lens, saving her from being blinded.

PC Luise Tait, 30, escaped with bruising and grazes but PC Ian Upperton, 31, suffered a gash across his forehead.

Both officers were shocked and were today recovering at their homes.

The two injured officers and their colleagues were investigating a burglary at a hair salon in Western Street, Brighton.

They went to arrest a suspect at a flat in Sillwood Place when they were attacked by a man who pulled a knife from his pocket.

The officers used pepper spray and stepped back, closing the door on the man while they waited for back-up.

The knifeman escaped through a window. Police dogs and the force helicopter joined a hunt but there was no trace of him.

Chief Inspector Lisa Pearcey, head of city centre policing, said the suspect's identity might be made public if he was not captured soon but she added: "We do not consider him necessarily a danger to the public."

The incident highlights the dangers police face every day.

Last week Special Branch officer Stephen Oake was stabbed to death in Manchester. In 2001 PC Gary Thompson was stabbed and seriously injured in Southwick.

It is understood that Sussex Police is about to make the wearing of new lightweight protective vests mandatory.

Senior officers, meanwhile, are urging the courts to treat offences of carrying weapons more seriously.

Chief Superintendent Doug Rattray, head of Brighton and Hove police, said: "I am deeply concerned by what happened and our thoughts are with the injured officers and their families. We wish them a speedy recovery."

Mr Rattray said light sentences were sending out the wrong message, adding: "Anyone who carries a knife and is prepared to use it against another member of the public or a police officer must be seen to be receiving stiff sentences."