Pedestrians have been left shaken after a woman was injured in a “freak” crash when a car crashed into a road sign, which collapsed on top of her.

The 37-year-old was walking in High Street, Wealdstone, when the black Ford Galaxy mounted the kerb and hit the sign, causing it to fall on the woman, who received serious head injuries, at 5.50pm on Monday.

The crash took place outside Pizza Royal, where witnesses who saw the were horrified.

Nashat Raouf, of Bishop Ken Road, Wealdstone, says his wife works with the victim, who he describes as a “very kind” woman.

He said: “It was very, very sad, and such a strange accident. I’m going to be looking at where I walk now.”

Hairdresser Vanessa Graham, who works at Hayley’s Nail and Beauty, was heading home from work at the time.

She said what should have been a ten-minute drive actually took over 45 minutes.

She said: “It’s so insane, people going about their everyday business and so many freak things happening. It’s just unfortunate.”

The driver was arrested on suspicion of causing serious injury by dangerous driving and remains in custody.

He has been released on bail until September, pending further enquiries.

Mother-of-three Collette Moriarty, of Claremont Road, said the helicopter landed near her home.

She said the shock of it left her three-year-old daughter feeling afraid.

She said: “It’s awful, it’s terrifying because it’s one of those things that could just happen to anyone.”