A baby boy who was crushed by a falling lamppost in Chiswick has died, police said today.

The tot, who has not yet been named, was pronounced dead at 5.30am today.

The youngster had been intensive care at the Royal London Hospital since Tuesday.

A postmortem examination will be scheduled in due course, a Metropolitan Police spokesman said.

A joint investigation is under way by officers from Hounslow CID and the Specialist Crime Directorate, and the Health and Safety Executive.

The baby was taken by air ambulance to the Royal London Hospital after the incident outside Chiswick town hall, just after 10.30am on Tuesday.

Horrified onlookers described how a 32ft lamppost fell on to the tot's push chair, crushing him inside.

The force of the impact was such that the pram broke in two.

A female carer who had been pushing the pram escaped injury.

An unrelated 62-year-old-woman, who was pinned under the lamppost, was taken by paramedics to Charing Cross Hospital with suspected spinal injuries. She was discharged yesterday.

A mum who saw the tragedy unfold and called 999 said her thoughts were with the family.

She said: "Right now the only thing I can think about is what his poor parents must be going through. It's terrible."

An inquiry is under way to find out whether construction work may have caused the lamppost to fall.

Health and Safety Executive inspectors have visited the site by Turnham Green, where building works have been carried out in recent weeks.

It has been reported that investigators believe the post's base could have been weakened by heavy machinery used to dig up the footpath.

On Tuesday afternoon Hounslow Council leader Peter Thompson, who is also a Turnham Green councillor, visited the scene.

A spokesman for the HSE said: “We are involved in a joint investigation with police and our inspectors have been on site.”

A Hounslow Council spokeswoman said the incident was an "awful tragedy" on Tuesday.

She said: "The council is cooperating fully with the police and health and safety executive investigations."