An experienced surfer has been killed by a shark in front of several people at a popular beach on Sydney's Northern Beaches.
The 57-year-old man was surfing with several friends about 100 metres off Long Reef in Dee Why when he was bitten by what police described as a "large" shark about 10am today.
Northern Beaches Police Area Command Inspector Stuart Thomson said he suffered catastrophic injuries and lost several limbs.
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The man and his board disappeared before he was found floating in the water.
Surfers pulled the man to shore but, despite efforts to save his life, he had lost a lot of blood and died at the scene.
Thomson said the man was an experienced surfer who lived in the area.
"We understand he leaves behind a wife and a young daughter, and tomorrow being Father's Day, it's particularly critical and tragic," he said.
Thomson described the attack as a "freak incident that happens very, very rarely" and a "terrible tragedy".
Several people were at the beach and its surrounds during the time of the attack, including competitors in a junior surf competition.
Beaches from Narrabeen to Manly have since been closed, and will remain so for at least 24 hours.
Dee Why is expected to remain closed for up to 76 hours.
Authorities were out in the water trying to find the shark, but were unable to do so.
Police and shark biologists from the Department of Primary Industries are examining the body, two sections of a surfboard that were recovered and speaking with witnesses to determine the species of shark involved.
Sydneysiders are urged to avoid beaches in the area as lifeguards keep people from entering the water.
Drone operators will be scanning the water for any signs of shark activity.
"Volunteers will continue to assist council and authorities to protect the public from further danger in any way we can," Pearce said.
"For now, please remain clear of the water at beaches in the vicinity and follow the direction of lifeguards and lifesavers."
Authorities offered their condolences to the victim's family and the wider community.
"There has been a tragic loss of life on one of our beaches, and our deepest condolences today are with the man's family and friends," Northern Beaches Council said.
"Our deepest condolences go to the family of the man involved in this terrible tragedy," Surf Life Saving NSW chief executive Steve Pearce said.
"The NSW government's thoughts are with the bite victim, their family and the first responders," a spokesperson for the Department of Primary Industries said.
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Shark attacks in Sydney are incredibly rare, with only one recorded fatality in the past 60 years.
Diving instructor Simon Nellist was killed while swimming off Little Bay Beach in the city's south in 2022.
The shark was confirmed later to be a great white.
Before that, the last fatal shark attack in Sydney was in 1963, when well-known actress Marcia Hathaway was fatally mauled by a bull shark while standing in 30cm of water in Middle Harbour.
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Shark nets came up for the season across 51 beaches between Newcastle and Wollongong on Monday.
There is a shark net in place off Dee Why Beach.
Three shark drumlines were set at Dee Why this morning, as per normal practice.
Crews have installed two more drumlines between Long Reef and Dee Why.
The Department of Primary Industries said sharks are present in the state all year round but can be more prevalent in an area due to weather, ocean conditions and availability of food.
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