A mountain-bike riding robber demanded money from his victim after striking him in a Brighton alleyway.
Police are appealing for witnesses after the attack in the alley between Powis Grove and Clifton Terrace, Brighton, some time between 10.15 and 11pm on Monday, February 8.
The 29-year-old victim was struck as the man cycled past. The man remained on his bike with his feet on the ground, as he demanded money from the victim.
The suspect is described as being white, aged around 30, slim build, wearing a black woolly hat, a black scarf over his nose and face, and a black jacket.
Anyone with information is asked to contact Sussex Police on 0845 60 70 999, quoting serial 1201 of 10/02, or anonymously to the independent charity Crimestoppers on 0800 555 111.