It’s the second suspected fatal shark attack in Australian waters this year.

Paramedics were called to the beach, just north of Forster, about 11:20am on Tuesday, after the man in his 50s was bitten while surfing.

Police say the man suffered serious injuries to his upper thigh.

He was pulled from the water but died despite the efforts of bystanders and emergency workers to revive him.

NSW Ambulance Inspector Joshua Smyth praised the bystanders who entered the water to bring the injured man ashore.

“Bystanders, including a retired paramedic, did a valiant job pulling the patient from the water and commencing CPR before paramedics arrived,” he said.

Surf Lifesaving NSW has closed beaches from Blackhead Beach to One Mile Beach for at least 24 hours, and the Department of Primary Industries is deploying smart drumlines at Tuncurry beach.

Drones have been deployed in the area, while photographs of the bite are currently being analysed by DPI scientists to try to determine the species and size of the shark.

There are reports a great white shark was detected at Main Beach on Monday.

Local lifesaver Brian Wilcox said the attack was “pretty unprecedented”.

“I can’t recall ever having a shark attack in this area,” he told ABC TV.

The DPI has advised water users and beach goers to follow the NSW SharkSmart Twitter feed or download the SharkSmart app for the latest information on shark movements and sightings.

Eight people were killed in shark attacks in Australian waters last year, according to the Taronga Conservation Society which records shark fatalities.

In January a Victorian man went missing in waters off Port MacDonnell in South Australia, and his torn wetsuit was later found, but his case was not recorded as an official shark fatality.