A 70-year-old man died in a changing room after going for a swim at Pavilions in the Park on Sunday (April 12).
Emergency services were called to the leisure centre in Hurst Road, Horsham just before 7.30pm after the man collapsed while using the changing room facilities.
Attempts to resuscitate him were made but he was pronounced dead at the scene.
A spokesperson for Sussex Police said it is believed the man, who is local, had been using the swimming pool.
The spokesperson added: “A post mortem is yet to take place. There are no suspicious circumstances.”
A South East Coast Ambulance Service spokesperson said: “We were called just before 7.30pm to Pavilions in the Park to reports a man had been found not breathing.
“We attended the scene with a community responder first, shortly followed by an ambulance car, an ambulance and one further car.
“Everyone including the duty manager worked to try to resuscitate the man.”