A STAB-proof vest saved the life of a security guard who was attacked outside Royal Blackburn Hospital.

Police have said his attacker, who tried to knife him just after midnight on Sunday into Monday morning, was not a patient at the hospital.

Detectives are now trawling through CCTV footage and investigating if the man has been treated at RBH previously.

The 29-year-old guard was wearing a high-visibility jacket over a stab-proof vest when he approached a man in the hospital grounds because he was ‘concerned’ for him.

He asked him if he needed help.

But the man pulled out a six to eight inch kitchen knife and thrust it at the guard.

However, it did not penetrate his skin because of the protective clothing. He then ran off.

The attacker is described as 5 feet 10 inches tall, with medium build, wearing a black hooded top, black tracksuit pants and white trainers.

His ethnicity is unknown.

DI Jill Johnston said police did not believe robbery was the motive.

She said: “It is only down to the protective clothing that the security guard was wearing that prevented him from being seriously injured.

“It is highly unusual for something like this in these circumstances to happen and I would reassure the public that we are treating this matter extremely seriously.

"We have a number of officers and staff working on the investigation to try and find the man responsible.

“I would appeal to anyone who may have witnessed the incident, or has information to come forward.

“The victim was not seriously hurt but he has been left shaken.”

The security guard, a local man, was back at work on Monday night.

Contact police on 0845 1 253545 or Crimestoppers anonymously on 0800 555 111.