Less than two hours later, two teenage girls were waist-deep in the water on another beach in Walton County when a shark bit them, according to the South Walton Fire District.

“This kind of incident can happen today, and then it might not happen for 20 or 30 years,” South Walton Fire District Chief Ryan Crawford said at a news conference Friday. The Walton County Sheriff’s Office said two shark strikes had been reported in the county between 2005 and 2023.

The first shark strike Friday occurred around 1:20 p.m., when a woman about 45 years old was bit near WaterSound Beach, according to the South Walton Fire District. Part of her left arm was later amputated as a result of her injuries, Crawford said.

The next shark strikes happened around 2:55 p.m. Friday near Seacrest Beach — about four miles east of the first incident, the South Walton Fire District said. One girl with injuries on her leg and hand was taken to a trauma center, officials said. The other girl had minor injuries on her foot and was taken to a hospital, according to officials.

“These people were hurt badly — life-threatening, life-altering,” Adkinson said at the news conference.

Gavin Naylor, director of the Florida Museum of Natural History’s shark research program, told The Washington Post that the presence of menhaden fish probably led to the strikes.

Sharks chased and ate the small fish as dozens swam near the shore Friday, Naylor said, and some beachgoers who were enjoying the water happened to be in their way.

“It's only when the sharks are feeding in waters where people are … that there's even the remotest chance that it happens,” Naylor said.

While experts have said that movies such as “Jaws” have portrayed sharks as antagonists, they rarely attack people. There were 69 unprovoked and 22 provoked shark bites worldwide last year, according to the Florida Museum of Natural History. Data showed that more people died as a result of falling into a hole at the beach than from shark strikes between 1990 and 2006.

Still, multiple shark strikes have occurred in the same areas before. At least four shark bites were reported near Long Island over two days last summer. Shark sightings have increased in recent years — a trend scientists have credited to conservation efforts.

David Vaughan, South Walton Fire District’s beach safety director, told CNN on Saturday that the same shark might have bitten all three people. But Naylor said that Friday’s strikes probably stemmed from two different bull sharks, which are common in the area.

He said one of the most unusual parts of Friday’s strikes were that they occurred in the afternoon. Most shark bites are reported in the morning or night, when their prey fish are most active, Naylor said.

“Nine times out of 10, the fish are jumping out of the water, sharks are following them, and there's kids in the water,” Naylor said, “and the sharks ignore them.”

Sharks might also accidentally strike people from confusion or curiosity, wondering what’s happening when they see a person moving in the water, according to the National Oceanic and Atmospheric Administration.

On Saturday, the Walton County Sheriff’s Office said that its marine unit saw a 14-foot hammerhead shark near Santa Rosa Beach while monitoring the area but that the sighting wasn’t unusual. Hammerhead sharks are usually not aggressive toward people, according to the Monterey Bay Aquarium.

County officials temporarily closed beaches to the public after the three strikes. When the beaches reopened Saturday, officials said they hung red and purple flags, which warn visitors of high hazards and dangerous marine life. The next day, they said, they lowered the hazard risks.

Naylor said beachgoers are typically safe from sharks, but they could encounter one if small fish are near the shore.

“When I see a whole bunch of little fish jumping out of the water close-in to the shore, it means that something’s chasing them, and it’s larger than they are,” Naylor said. “And it could be a shark. So I tell [people], ‘Hey, come on in for a while. Let’s give it half an hour until the fish stop jumping.’ ”