Emergency Medical Services transported a swimmer to the hospital after he was found unresponsive in waters off of Kaimana Beach.
The swimmer described to be in his 60s to 70s is a participant in the 48th annual Waikiki Roughwater Swim. The 2.384 mile-race starts at Kaimana Beach and ends at Hilton Hawaiian Village.
Lifeguards hired by event organizers brought him to shore at about 9 a.m.
Ocean Safety lifeguards and two companies of the Honolulu Fire Department responded and performed CPR on the swimmer. EMS also performed advanced life-saving procedures until he regained a pulse.
He was transported to a hospital in critical condition.