Rescuers are searching for a person who disappeared after reports of a shark in Hawaii.
On Thursday, police in Maui received a call from a man who "saw a shark swim by repeatedly" while he was snorkeling 50 yards from Keawakapu Point, Hawaii Department of Land and Natural Resources senior communications manager Dan Dennison said in a news briefing on Thursday.
After spotting the shark, the man — whose identity was not released — searched for his wife and went back to shore after he was unable to find her, Dennison said.
He confirmed that there was "an ongoing search for a person who possibly encountered a shark earlier today."
According to Hawaii News Now, the husband told police that he and his wife fought the shark before trying to go back to safety. While the man made it to shore, his wife did not. Later, part of a bathing suit and snorkeling set were recovered, per the outlet.
The Maui Fire Department and Maui Ocean Safety officers have begun looking for the woman in the water and through an aerial search, Dennison said.
"At this time, they have not spotted anyone in the water," Dennison said, adding that authorities planned to keep searching "until nightfall." The area is closed until authorities re-evaluate the matter in the morning.
He noted that in the meantime, people should "stay clear of the area" both on land and in the water.
Dennison said they are unable to share any information about potential victims due to policies on shark-related incidents.
"Once we have that information, we will share it with the media," Dennison said.
Asked about items that had been found in the area, Dennison said authorities "could not confirm" whom they belonged to.
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He added that he also cannot confirm that the man's wife is whom rescuers are searching for, stating that the incident is being described as "a possible shark-human encounter." The missing individual was last seen just before noon.
"You can kind of connect dots, but that's what we would presume," said Dennison.
There have been no other sightings of the shark since the man's initial report, Dennison said, adding that Maui "has the most human-shark encounters of the main Hawaiian islands."
"There's not a lot of information to release now because they don't know exactly what they're dealing with," Dennison added.
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Dennison went on to share experts' warnings on how to avoid encounters with sharks.
"Don't go in the water if it's murky. I have no idea what the ocean conditions were in that area this afternoon. Don't go in after dark, before sunrise. Always swim or snorkel...in the ocean with a companion," he said.
He added that agencies have "a significant number of people" looking for the individual, stating, "This is a very fluid situation. We're all hoping for a good outcome. The search has been going for almost five hours now. They'll continue in earnest for...about another hour or so."
Dennison tells PEOPLE there is nothing further to add.