A 31-year-old Pahoa man was found submerged Sunday morning in the ocean off Kona, according to Hawaii island police, who are investigating the case as a possible drowning.

Police and fire personnel responded to a call just before 11 a.m. Sunday at the 75-5700 block of Alii Drive in Kailua-Kona.

Witnesses told officers the man was seen submerged in the ocean about 50 to 100 feet from shore, that he had not come up for air for over 10 minutes, and appeared to have no diving equipment.

Hawaii firefighters retrieved the unresponsive man from the water, and first responders transported him to Kona Community Hospital, where he was pronounced dead.

Police, who have initiated a coroner’s inquest investigation, suspect no foul play at this time.

The man’s identity is being withheld pending notification of next of kin.

Police ask anyone with information to contact Kona Patrol Officer Elijah Won at 808-935-3311 or elijah.won@hawaiicounty.gov.