A man has been killed by a shark while diving with his brother off the coast of southwestern Australia in the fourth fatal attack in the country since last September.
Businessman Peter Kurmann, 33, and his brother Gian, 34 were diving from a boat off Stratham Beach, around 140 miles (230km) south of Perth, when the younger man was attacked.
The diver's brother dragged his body into the boat and drove it back to shore
State police spokesman Sergeant Naomi Smith said the diver, from the nearby town of Vasse, was apparently killed instantly.
His brother, who was unharmed, is reported to have dragged his body back into the boat and driven it back to Port Geographe Marina, near Busselton.
The Western Australia Fisheries Department has launched an investigation, which will include an examination of bite marks on the victim's body, to determine the shark species.
Department manager Tony Cappelluti said Gian Kurmann had reported seeing "a four-meter (13ft) dark, shark-like shape" in the water.
An air surveillance team later spotted a shark in the area and a boat equipped with capture gear has been sent to the scene.
It had initially been thought the attack happened around 200m from the beach but the authorities later said it was actually about a mile from the shore.
Experts have been unable to explain the spate of attacks in Australia's South West, but agree that different sharks are likely to have been responsible for each fatality.
The last fatal attack in Australia was American George Thomas Wainwright, 32, who was killed by a great white on October 22 as he dived near Rottnest Island, near Perth.
A great white of the same size is believed to have killed 64-year-old Australian swimmer Bryn Martin off Perth's premier Cottesloe Beach on October 10.
On September 4, bodyboarder Kyle Burden, 21, was also killed by a shark witnesses said was 4.5m (15ft) long, although the type was never confirmed.
Australia averages little more than one fatal attack a year, although they have become more common in recent decades as the population rises and more people take to the water.