A man is fighting for his life after being his by a motorcyclist in east London.
The pedestrian, whose age is not yet known, was hit outside Mile End station just after 12.30pm, police said.
A spokeswoman added: "Both parties are injured. The motorcyclist's injuries are not thought to be serious.
"The pedestrian has serious head injuries, which are currently assessed as life-threatening."
Witness George Bruce tweeted after the accident: "Nasty accident at Mile End station. Road closed Eastbound. #airambulance on scene."
Another witness posted: "Someone got knocked down at Mile End station."
The junction with Mile End Road and Burdett Road has previously been criticised as dangerous by campaigners who cite its slip roads and volume of traffic and pedestrians using it.