Update, 2.50pm: Surf lifesavers have rescued about 30 people from a rock off Twilight Beach today after reports of a 5m to 6m white pointer in the area.
Twilight Beach was closed between 11.15am and 12.30pm after a helicopter tour group spotted the shark.
A Surf Life Saving WA spokesman said 30 people were taken by boat from Twilight Rock to the mainland as a precaution.
“It’s a big rock about 100m off the beach,” he said.
“We didn’t really want them to swim in.”
Local rangers and the Department of Fisheries are at the scene.
A department spokeswoman said fisheries officers were patrolling the area but had not been able to confirm the sighting.
“The Department of Fisheries boat went out there but they haven’t seen the shark again,” she said.
A department spokeswoman said the tour group was doing a fly-by of the bay when they spotted the shark.
Three sharks have also been spotted 200m off shore at Bunker Bay in the Margaret River region.
The sharks, which are all about a metre in length, were spotted from the South-West Rescue Helicopter.
A Surf Life Saving WA spokesman said the sharks were feeding on bait schools.
He said the beach had been cleared and there was no one in the water.
The species of shark has not yet been confirmed.
A 2.5m tiger shark has also been spotted at Gas Bay, tracking north and a 2m shark was sighted 1km off Maidens Beach in Bunbury at 8.35am. The shark was seen heading south.
Bunker Bay beach was closed yesterday after eight Hammerhead sharks ranging from 2-3m were seen in the water.
Surf Life Saving WA tweeted at 10.15am that two sharks had been spotted by the South West rescue helicopter.
One, measuring between 2m and 2.5m, was 100m off Gnoocardup at 9.45am. The beach was cleared.
A 1.5m shark was 50m offshore at Kilcarnup heading south-west.