A day in the water turned tragic after an Australian teenager was killed by a shark off Australia’s east coast. The 19-year-old body boarder suffered a heart attack after a shark bit his legs. The Weather Channel reported that this is the second deadly shark attack in Australia this month.

According to Sky News, Zack Young and his friends were body boarding at Riecks Point near Coffs Harbor, New South Wales, a popular surf spot about 280 miles north of Sydney. They were sitting upright on their boards about 300 feet from the shore when a shark latched onto both of Young’s legs. The teenagers struggled with the shark for a few moments until it let go.

According to authorities who responded to the shark attack, Young’s friends “courageously” buoyed the injured teen back to shore after he was attacked. The Australian Broadcasting Corp. News reported that the shark attack caused Young to lose a lot of blood, but that he ultimately died from traumatic cardiac arrest.

"Attempts were made to resuscitate him when he was brought to the shore, but he died at the scene," a New South Wales ambulance spokesperson told ABC News.

Authorities believe it was a bull shark, which some experts believe to be the most dangerous shark in the world, that attacked Young. But they won’t be sure until they can get forensic analysis of the bites.

"It's very, very unusual. We don't know details of what type of shark it is yet, but it could be a rogue shark that has just been traveling through the area,” Coffs Harbour Council lifeguard team leader Greg Hackfath told ABC News. "He could have just been at the wrong place at the wrong time. We will probably never know that."

The deadly shark attack on Young comes just a week after 35-year-old surfer and father of two Chris Boyd was killed by a shark off Gracetown, about 170 miles south of Perth.

Sharks are common off the Australian coast, but fatal shark attacks are actually quite rare. Before last week, the latest deadly shark attack in Australia occurred in July 2012 when a surfer was bitten in half in the waters near Wedge Island. That attack, the fifth in a spate of attacks by great white sharks near Wedge Island, set off a controversial culling of sharks in that area.