A shark ripped off part of a 15-year-old tourist's leg on Saturday as he swam at a beach in Australia's remote southwest, officials said.

Zak Golebiowski, from South Australia state, was attacked as he bodysurfed with a brother and a friend about 40 yards offshore at Wharton Beach, said police Constable Katrina Luke.

The teen's right leg was severed above the knee and his left leg badly mauled, but family members and witnesses on the beach managed to stem the bleeding until an ambulance arrived, Luke said.

He was later flown to Royal Perth Hospital for further treatment and was in a serious but stable condition, Luke said.

The beach, which is located about 435 miles south of the Western Australia state capital of Perth, was closed until further notice.

Scientists say there are an average of 15 shark attacks a year in Australian waters — one of the highest rates in the world — and just over 1 per year are fatal.