A 24-year-old man has been arrested after a collision between two jet skis left one of the riders badly injured on Sunday (August 25).
A spokesman for Sussex Police said they are investigating a collision between two jet skis in open water just outside the entrance to Shoreham Harbour in Southwick.
The spokesman said South East Coast Ambulance Service informed officers of the crash at around 4.47pm, during which one of the riders had been badly injured.
Officers and detectives spoke to witnesses and seized the jet skis, the spokesman added.
A 19-year-old man from London was taken to Royal Sussex County Hospital in Brighton where he was treated for his injuries, the spokesman said, and remains under observation.
A 24-year-old man, also from London, was arrested on suspicion of committing grievous bodily harm and was released under investigation pending further enquiries, the spokesman said.
The Marine Accident Investigation Branch has been informed of the incident.
Anyone who witnessed the incident is asked to report it online or call 101, quoting serial 956 of 25/08.