A surfer was killed in a savage shark attack off Australia's west coast, officials said, the fifth such fatality in the region in less than a year.
The man was surfing near Wedge Island, north of Perth, on Saturday morning with a friend when he was mauled by the shark, suffering severe and extensive injuries.
Beach patrol officials confirmed that the attack was fatal, and a large-scale air, coast and sea search was underway for the remains of the victim, who was reported to be in his early 20s.
A police spokesman told AFP: "At this stage no remains have been located."
It is the fifth fatal shark incident off Western Australia since September -- an unprecedented number that sparked calls earlier this year for a cull.
Local marine scientists have described Australia's west coast as the deadliest shark attack zone in the world, and a tagging and tracking programme has been launched in a bid to limit fatalities.
A sea kayaker narrowly escaped the jaws of a great white shark last month, with a friend managing to pluck him from the water after he was rammed by one of the marine predators off Perth's Mullaloo Beach.
That attack came just hours after another great white, thought to be five metres (16 feet) long, lunged from the water at a crab fisherman at a dive park south of Perth.
Sharks are common in Australian waters but deadly attacks are rare, with only one of the average 15 incidents a year typically proving fatal.
Experts say the average number of attacks in the country has increased in line with population growth and the popularity of water sports.