POLICE have closed the A4 near the Hogarth Roundabout in Chiswick following a serious accident at about 9.30am this morning.
The Chronicle understands the Great West Road is closed westbound at Hogarth Lane near the junction with Sutherland Road.
Congestion is already building back beyond the Hammersmith Flyover. An ambulance is at the scene.
A London Ambulance spokeswoman said: "We were called just after 9.30am on Tuesday (13) to reports of a road traffic collision involving two cars in Sutherland Road, Chiswick.
"We sent an ambulance crew to the scene who arrived in six minutes. We treated a man reported to be 31 years old for leg and back injuries. He was given pain relief, collared and bordered on the scene and sent to St Mary's Hospital trauma centre."