A young British woman was killed in front of horrified shoppers on Thursday when a giant window frame fell on top of her as she walked past a building site.

A gust of wind dislodged the concrete frame and hit the smartly dressed redhead, thought to be an office worker in her mid-20s.

Passers-by and construction workers at the multi-million-pound six-storey office block, off Oxford Street in Central London, battled to resuscitate the woman but she was declared dead at the scene.

On Thursday night witnesses claimed the “very heavy” window had been left “propped” on a wall on the ground floor, and that barriers guarding the building site had recently been removed.

The accident happened at 11.30am in Mayfair’s Hanover Square, which houses some of London’s most expensive offices. An art gallery is on the ground floor and the Vogue building, the headquarters of publisher Conde Nast, is opposite.

Dario Motti, 65, said the 3.5-metre high frame had been propped up against a wall before it fell on the woman. “I saw the frames delivered yesterday,” he added. “They were so heavy they were lifted in by crane.”

Kohei Matsumoto, manager of a nearby Itsu sushi restaurant, added: “Two of my team members saw a girl turn left into Hanover Street. She was eating a banana.

“The next thing they saw was this window frame falling down on her. She didn’t scream – it happened so quickly.”

A man delivering electrical cables to another building, who did not want to be named, said that it had taken ten people to lift the frame off the woman.

“I heard this incredible loud bang,” he said. “I turned round and the frame was on the ground. I was hoping it was a coat underneath – but then I saw an arm.

“There was a woman who said she was a doctor who wanted to perform CPR, and somebody was giving her mouth-to-mouth.

“Her eyes were open and I saw her hand move and then I saw her last breath, and then the light went out – she’d gone. She was in the wrong place at the wrong time.’

Beverley Hazel, from Kennington, South London, was on her way to work at 11.30am when she saw the woman lying in the road.

She said: “She was very young and slight. I’ve got two daughters, one younger and one older than this woman. I was in bits. If it had been my daughter I would have wanted someone with her.”

A spokesman for Westgreen Construction Ltd, of Richmond-upon-Thames, Surrey, which is managing the building project, said: “We will do whatever is necessary. This is a terrible accident.”

The woman’s body, which had been covered by a yellow police tent, was removed by a private ambulance at 6.45pm on Thursday.

The Health and Safety Executive said it was “making initial inquiries”.

A Metropolitan Police spokesman said hat the investigation was “ongoing”. - Daily Mail