A cyclist suffered serious head injuries after being involved in a collision with a milk float in Maderia Drive, Brighton, today (Tuesday 26 July) at 8.20am.
Sussex Police said that his injuries were life threatening.
The milk float driver, a 22-year-old man, has been arrested on suspicion of dangerous driving and is currently in custody.
The road, at the junction of Dukes Mound, remains closed.
Anyone who saw the collision is asked to contact Sussex Police on 0845 6070999.