An investigation is under way after a man died when he was hit by a metal sign which fell from a betting shop.

The man, who is believed to be in his 20s, died yesterday in Camden, north London.

A sign covering the length of a William Hill bookmakers in Camden Road fell to the pavement, hitting the man.

He was treated at the scene for a head injury but died later in hospital, London Ambulance Service (LAS) said.

"Every effort was made to resuscitate him at the scene and on the way to University College Hospital," an LAS spokeswoman said.

Police cordoned off the area and forensics officers examined the scene where the man died. Health and safety investigators also entered a flat above the shop to take photographs of the sign, which was made of metal and measured approximately 30ft.

Last night a bunch of flowers was left at the scene by a member of the public as a mark of respect.

A William Hill spokeswoman said: "There is an urgent investigation under way and we are still establishing facts and liaising with authorities.

"As such, we don't have a comment to make at this time."

Ioana Nita, 21, was working at a nearby restaurant when the accident happened at 4.55pm.

"I'm shocked. We heard a very loud noise. Me and a colleague went outside and saw the guy lying on the floor," she said.

"Five guys picked up the sign and it was put on the side. His hands were covered in blood and he wasn't moving.

"Lots of people were in a circle around him, then the ambulance arrived and they were trying to get him back to life, pressing on his heart."

She added: "I just want to go home and cry. I don't know how that can happen. The sign is huge. Everyone said he was just walking past the shop.

"I cross that way five times a day. That could have been me."

Ken Osbourne, 28, who works at the nearby Woody Grill restaurant, said: "I saw the guy lying down in the road, covered in blood.

"The main impact was clearly on his head. I saw them trying to resuscitate him in the back of the ambulance."

Mr Osbourne added: "Hundreds of people walk past here every day. It could've been me or any one of them. The shop has been there for about 10 years."

A Scotland Yard spokesman said: "Officers and London Ambulance Service attended and the man, believed to be aged in his 20s, was taken to a central London hospital for treatment. He died there a short while later.

"At this early stage it appears the man received his injuries after being struck by a sign or board which has fallen from a building."