A diver was hospitalised on Tuesday after finding himself in difficulty in Gozo.
Police said they were informed of the incident at around 3.30 pm after a 51-year-old Polish national was admitted to Gozo General Hospital.
He was certified as being in serious condition.
Initial investigations suggest that the man was diving in the vicinity of ix-Xatt l-Aħmar when he found himself in difficulty.
He was given first aid by his companions, who later took him to hospital for medical assistance.
Duty magistrate Brigitte Sultana has opened an inquiry into the incident.
A police investigation is ongoing.