An explosion caused by lava oozing into the ocean sent a lump of molten rock crashing through the roof of a sightseeing boat off Hawaii’s Big Island, injuring 23 people.
A woman in her 20s was in serious condition with a broken thigh bone after being hit by the “lava bomb”, the Hawaii County Fire Department said.
Three others were in stable condition at a hospital with unspecified injuries. The rest of the passengers suffered burns, scrapes and other superficial injuries.
They were aboard a tour boat that takes visitors to see lava plunging into the ocean from a long-erupting volcano that has been vigorously shooting molten rock from a new vent in the ground for the past two months.
The lava punctured the boat's roof, leaving a gaping hole, firefighters said.
Shane Turpin, the owner and captain of the vessel that was hit, said he never saw the explosion that rained molten rocks down on top of his boat.
He and his tour group had been in the area for about 20 minutes making passes of the ocean entry about 500 metres offshore, he said.
“As we were exiting the zone, all of a sudden everything around us exploded,” Mr Turpin added: “It was everywhere.”
Mr Turpin said he had no idea just how big the blast was until he saw video of the event later on shore.
“It was immense,” he said. “I had no idea. We didn't see it.”
The captain has been navigating lava tour boats for many years and has lived on the Big Island since 1983.
He said most of the injuries were minor, but that he had just visited one woman who sustained serious injuries in the hospital.
“They're unbelievable people,” Mr Turpin said of the woman and her family, who are visiting the island. “Just really good people.”
Officials have warned of the danger of getting close to lava entering the ocean, saying the interaction can create clouds of acid and fine glass.
Despite the hazards, several companies operate such tours. The Coast Guard said tour vessels have operated in the area going back at least 20 years.
The US Coast Guard in May instituted a safety zone where lava flows into the ocean off the Big Island. It prohibits vessels from getting closer than 300m (984ft) from ocean-entry points.
The agency allows experienced boat operators to apply for a special license to get up to 164 feet (50 meters) from where lava sizzles into the sea.
The molten rock is coming from the Kilauea volcano, which has been erupting continuously for the past 35 years.
In May, its eruption entered a new phase when it began spurting lava through newly formed fissures in a residential neighbourhood.
It has destroyed more than 700 homes since then. But the only serious injury over the past two months was to a man who was hit by flying lava that broke his leg.
Officials were interviewing injured passengers at a hospital.
Additional reporting by Reuters
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