A shark bit a Maui surfer Friday and severed his leg, authorities said.

The 61-year-old man was surfing near Waiehu Beach Park on Friday morning when a shark bit him. The police who arrived at the scene first tried to control the bleeding with a tourniquet.

His right leg was “completely severed just below the knee,” Maui County said in a news release.

The man was alert while being treated on shore and then taken to Maui Memorial Medical Center in critical condition.

The man said he did not see the shark approach, authorities said.

The incident prompted authorities to close the beach park.

Authorities warned people not to take water in the area.

The public advisory to stay out of the water one mile in each direction of the incident will be in effect until at least noon Saturday.

The warning will be extended if a shark is sighted in the area.

Maui firefighters and ocean safety officials were patrolling the waters using rescue boats and a drone.

State officials provided shark warning signs and helped cordon off the area.

No details were provided on what kind of shark was involved.

In June, well known surfer Tamayo Perry was killed in a shark attack while sailing on the north coast of Oahu.