(BIVN) – A search for a missing cruise ship passenger from Australia is ongoing, 500 miles south of Kailua Kona.

The U.S. Coast Guard said its Joint Rescue Coordination Center Honolulu received a report of a man overboard at 11:03 p.m. Tuesday from the cruise ship Quantum of the Seas. The crew of the cruise ship remained on scene to search for approximately two hours, deploying six life rings, the USCG said.

A Coast Guard Air Station Barbers Point C-130 Hercules aircrew launched at 7 a.m. and arrived on scene at approximately 9 a.m. to begin searching, a news release stated. “After six hours on scene, the crew returned to Air Station Barbers Point for fuel replenishment,” the USCG said. “The search will resume at first light Thursday morning.”

The cruise ship has been at sea for 15 days and is expected to dock in Honolulu on Friday, Coast Guard officials say.