A bull shark likely behind fatal attack of 16-year-old girl swimming in a river, say authorities

• Authorities in Perth, Western Australia, believe that a bull shark is responsible for a fatal attack.

• 16-year-old Stella Berry was killed in the Swan River in Perth.

• Bull sharks, which can live in salt and fresh water, can be aggressive though fatal attacks are rare.

Authorities in Perth, Western Australia, believe that a bull shark could be responsible for the attack that killed a 16-year-old who went jetskiing with friends.

The Australian fisheries minister Don Punch said that it was too early to confirm the species of shark responsible for the fatal attack in the Swan River but told ABC News that he believes it may be a bull shark.

"We do know that bull sharks, particularly, do enter estuaries and freshwater river systems, so it is likely that may be the case," he said.

Bull sharks are the most dangerous sharks in the world, according to many experts, because they hunt along shorelines where people gather to swim. The species also inhabits freshwater rivers increasing the chance of encounters with humans. They have been known to travel up the Mississippi as far up as Illinois, for example, a distance of  700 miles.

One or more bull sharks may have been responsible for the famous 1916 Jersey Shore shark attacks that inspired Peter Benchley's novel "Jaws."

One of the biggest bull sharks recorded was 13 feet long and weighed 990 pounds.