A MAN was forced to hand over rings and his rucksack after being threatened with a needle.
The victim was walking through an alleyway near a park when he was approached by two men on bicycles.
One of them brandished a needle and the man had to hand over valuables.
The pair rode off from the alleyway at the side of Hotham Park in Bognor Regis.
Police are appealing for witnesses following the robbery, which happened at about 3pm on Tuesday.
The first suspect is white, aged between 25 and 28, around 5ft 7in, of slim to medium build, with shaved blond or light brown hair.
He had bad skin, was scruffy in appearance and wore black tracksuit bottoms. He spoke with an Eastern European accent and rode a red mountain bike.
The second man was white, aged between 25 and 30, muscled with broad shoulders, with short brown hair and brown stubble. He had tattoos on both forearms. He rode a dirty BMX bike. Call police on 101.