A 16-year-old boy mauled by a shark off the North Carolina coast spoke from his hospital bed at the New Hanover Regional Medical Center in Wilmington on Tuesday (16 June) about his harrowing ordeal, but said it would not bring his spirits down.

"I've lost my arm, obviously, so I have kind of two options. I can try to live my life the way I was and make an effort to do that, even though I don't have an arm, or I can kind of just let this be debilitating and bring my life down and ruin it, and out of those two, there's really only one that I would actually choose and that's to try to fight and live a normal life with the cards I've been dealt," Hunter Treschl said just two days after the attack that occurred in Oak Island.

"I was in about waist-deep water, playing with my cousin, and I felt this hit on my left leg, it felt like it was a big fish coming to you or something. Then I felt it like one more time and it just kind of hit my arm, that is the first I saw it [the shark] was when it was biting up my left arm, then it got that off," he said.

In Oak Island, swimmers were urged to be vigilant after Hunter lost his arm and a 12-year-old girl lost part of an arm in the Sunday attacks, which occurred about two miles apart on the same stretch of beach. The attacks occurred in waist-deep waters about 20 yards offshore.

No additional information was available about the girl, whose family has requested privacy, the hospital said.

The twin attacks Sunday were extremely rare, with only two similar incidents recorded in the past four decades – one in Egypt and another in the Florida Panhandle, said George Burgess, director of the International Shark Attack File database maintained at the University of Florida.

But 2015 is off to a deadly start, with six fatalities already reported worldwide, including one in Hawaii, said Burgess's assistant Lindsay French. In 2014, three fatalities were recorded internationally.

The attacks occurred at the start of the summer tourist season at Oak Island, a town of about 7,000 year-round residents that gets 40,000 visitors over the 4 July holiday weekend.

Officials could not confirm whether the attacks involved one shark or two, but noted that shark encounters in the area were so rare that last was believed to have occurred decades ago.