Shark Attacks: Two Teenagers Lose Limbs on North Carolina Beach

Two separate shark attacks just a few miles apart on Sunday severely wounded two young people and shattered an otherwise tranquil North Carolina beach town's summer weekend.

The two teenagers were attacked as they swam in waist-deep water two miles apart and each about 20 yards off the shores of Oak Island, a self-described "family friendly beach community with a small town atmosphere."

Oak Island's mayor Betty Wallace, told CNN that the shark first attacked a 12-year-old girl, at around 4:15 pm. Ninety minutes later, as first responders were still tending to the girl, a shark struck again - possibly the same one - this time attacking a 16-year-old boy.

Officials say both victims were on vacation, visiting the coast from other parts of North Carolina. They were both airlifted to New Hanover Regional Medical Center in Wilmington and were in critical condition upon arrival, says hospital spokeswoman Martha Harlan.

Harlan says both victims have had an arm amputated; the boy's below the shoulder, the girl's at the elbow. Harlan also said the female victim suffered serious tissue damage to her leg. Both have since been upgraded to fair condition, officials say.

Brunswick County Emergency Services director Brian Watts credited their survival to bystanders who helped to stanch their bleeding and the quick work of emergency personnel.

"Without that, we would have had a different outcome," he said.

So far, it is unclear whether the same shark attacked both victims. Brunswick County Sheriff John Ingram said two sharks were spotted a few hours after the attacks.

"We spotted one shark that was estimated over 7 feet long between the locations of the two bites earlier, and then we spotted another one off, down a little further south, about the same size," Ingram told reporters Monday morning.

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Steve Bouser was on the beach Sunday when the first attack occurred.

He said there was suddenly a commotion and people started saying "get out of the water, get out of the water." Then, he says he saw someone carrying a female with "some terrible wounds" to the shore.

"You've got this nice beach scene going on," Bouser told a reporter from Star News Online, "and the next moment is just a nightmare."

Officials say they sent an all-terrain-vehicle and people with megaphones to get everyone out of the water after the attacks.

Oak Island Mayor Betty Wallace told The Associated Press that the window of less than two hours between attacks didn't give workers enough time to close down the town's beaches, but they were closed after the second attack.

Wallace says that even if the beach had closed after the first attack, the order might not have reached the area where the second victim was bitten.

In a press conference following the incidents, the Oak Island Town Manager Tim Holloman assured people that neighboring Brunswick County and Oak Island were working to assess the situation using marine and helicopter support.

Harlan told Star News Online that "shark attacks like this are very rare." However, just last week, a 13-year-old girl was bitten by a shark while boogie boarding at Ocean Isle, North Carolina, just 30 miles south of Oak Island. She suffered only minor injuries to her foot. According to data provided by the Shark Research Institute, there has been an increase in non-fatal, unprovoked shark attacks in the state of North Carolina over the last 15 years.

According to CoastWatch, the coastal waters of North Carolina lie along a major migration corridor for many marine species. There are 14 species of sharks commonly found in North Carolina waters. During the summer months, species such as Blacktip Sharks will migrate north in schools from Florida to cooler waters around Cape Cod, Massachusetts. Blacktips are known to prefer shallower, inshore waters.

Shark attacks are still extremely rare. Since 1900, there have only been 156 fatal, unprovoked incidents. Fire Chief Chris Anselmo told CNN that Oak Island's beaches will remain open on Monday, but that swimmers are advised to stay close to the shore.

There were 72 unprovoked shark attacks around the world in 2014, including 52 in the U.S., according to the International Shark Attack File at the Florida Museum of Natural History. Three of the attacks, all in other countries, were fatal.

The Associated Press contributed to this report