SYDNEY -- A surfer was killed by a shark on Tuesday off the Australian east coast, police said.

The man, aged in his 50s, had been surfing off Forster, 220 kilometers (137 miles) north of Sydney, when he was attacked late in the morning, a police statement said.

Onlookers pulled the man from the water suffering critical injuries to his upper right thigh, police said.

The Ambulance Service said the man could not be resuscitated despite the best efforts of paramedics and bystanders at the scene.

Forster beaches have been closed.

Police said they were working with government authorities to identify the species of shark.

Lower North Coast Surf Life Saving branch president Brian Wilcox said a drone search after the attack had spotted two sharks in the area.

"It's pretty unprecedented. I can't recall ever having a shark attack in this area," Wilcox told Australian Broadcasting Corp.

"We'll ... do drone missions for the next couple of days, within the Tuncurry Beach area, just to make sure there are no sharks hanging around," Wilcox added, referring to the beach where the surfer was attacked.

The man's name has not been released.

It was the first fatal shark attack in Australia since November when a 55-year-old surfer was mauled near the northwest town of Broome.