An explosion caused by lava oozing into the ocean sent molten rock crashing through the roof of a sightseeing boat off Hawaii’s Big Island, injuring 23 people Monday, officials said.
A woman in her 20s was in serious condition with a broken thigh bone, 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 lava 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.
WATCH: Lava bomb from Kilauea hits Hawaii tour boat, injuring 23 passengers
He and his tour group had been in the area for about 20 minutes making passes of the ocean entry about 500 yards offshore, Turpin said.
He didn’t observe “any major explosions,” so he navigated his vessel closer, to about 250 yards away from the lava.
“As we were exiting the zone, all of a sudden everything around us exploded,” he said. “It was everywhere.”
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.”
WATCH: New cell phone video has emerged following the explosion that caused molten rock to barrel through the roof of a Hawaii tour boat. The new video was shot from that tour boat that was hit.
Turpin says that he has been observing and documenting these explosions and that this type of activity is new. There were no warning signs before the blast, he said.
“There’s something new. There’s something really new,” he said. “And I’ve been documenting them a bit.”
Turpin 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,” he said of the woman and her family, who are visiting the island. “Just really good people.”
The others in the tour group quickly pulled together helped one another, Turpin said.
“What I saw in humanity this morning was amazing. I mean this was a group of people that never met before, and they were brought together,” he said. “In all honesty, we definitely evaded a catastrophic event today.”
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 U.S. 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 984 feet (300 meters) 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 neighborhood. 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.