A father and experienced surfer has been killed by a shark in front of several people at a popular beach on Sydney's Northern Beaches.
Mercury Psillakis, 57, 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 Commander Superintendent John Duncan said Psillakis suffered catastrophic injuries and lost several limbs.
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Psillakis and his board disappeared before he was found floating in the water.
Surfers pulled him to shore but, despite efforts to save his life, he had lost a lot of blood and died at the scene.
Psillakis' wife and daughter rushed to the beach after hearing the news. His brother, Mike, arrived shortly after.
"We understand he leaves behind a wife and a young daughter, and tomorrow being Father's Day, it's particularly critical and tragic," Duncan said.
Psillakis was an experienced surfer who lived in the area and never missed a morning out on the waves.
Sean Pearce paid tribute to his friend, who lived life travelling the world, surfing, spending time with his family and working.
"He was a good bloke to everyone. You couldn't find someone to say a bad word about him," Pearce said.
"When I grew up, he was always one to help out the grommets."
Authorities offered their condolences to Psillakis' family and the wider tight-knit 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.
Premier Chris Minns said this was an "awful tragedy".
"My heart goes out to the victim's family and friends," he said in a statement.
"I also want to thank the first responders and community members who tried to help in such tough and confronting circumstances.
"Shark attacks are rare, but they leave a huge mark on everyone involved, particularly the close-knit surfing community."
Duncan said the attack was a "freak incident that happens very, very rarely".
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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