A great white shark has been filmed attacking a fishing boat off the coast of Western Australia.

The shark, which measured about five metres in length (16.4ft), circled the small boat, then threatened to capsize it by attacking the outboard motor.

The three fishermen on board were not hurt and made a quick escape from the area, near the town of Busselton.

Two of them had been swimming in the same spot about an hour earlier, according to local reports.

Fisherman Mark Kik said the predator "kind of circled us quite a number of times, then it looked as though it was taking off, so it took off in the distance".

"But within a short period, it was back again and circled around the boat again and then did a very quick U-turn and that's when it grabbed the motor," he added.