An explosion at the Ala Wai Yacht Harbor sent a man to the hospital with serious injuries.
The incident happened at about 9 a.m. Monday on board a 43-foot sport yacht.
Fire officials say two men were on board at the time of the explosion. The other man was not hurt.
Officials say it appears the explosion was related to some sort of flammable vapor.
"There was perhaps a fire with the explosion, but when we got here there was no longer an active fire burning. But there was a little bit of smoke," Honolulu Fire Department Capt. Terry Seelig said.
According to Emergency Medical Services, a 58-year-old man sustained second-degree burns. He was treated and taken to the hospital.
The explosion did not damage any other yachts.
Damage to the boat is estimated at $100,000.
The exact cause of the explosion is under investigation.
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