A teenager was threatened with a gun while walking along Brighton seafront.
The 17-year-old victim was walking near the West Pier along King's Road when he was approached by a man with a gun who demanded money, Sussex Police said.
The teenager refused and ran away. Officers are carrying out forensic tests on a handgun recovered nearby.
Police said the suspect was a white man in his early 30s. He was of chubby build and wore a black hooded jumper, beanie hat and white T-Shirt.
Sussex Police appealed for witnesses to the incident, which happened in the early hours of Sunday.