The state government has paused a planned trial to take down shark nets from Sydney beaches after a man was killed in fatal shark attack yesterday.

Experienced surfer Mercury Psillakis, 57, suffered catastrophic injuries and died at the scene after being mauled by a "large" shark about 10am while surfing at Long Reef Beach near Dee Why.

A NSW shark net trial to remove three nets this summer has now been halted, NSW Premier Chris Minns has confirmed.

"We need to understand what happened and how it happened," Minns told Sky News, after describing the attack as an "awful tragedy".

"I think it's also worth reporting that Dee Why is a netted beach and was not going to be part of the trial, so I need to understand whether the shark got inside the nets or how the system's operating, befo

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