Up to 60 killer whales have torn apart a lone beaked whale off the coast of Australia.

Paul Cross from Naturaliste Charters, who was on the boat on Saturday, said more than 40 tourists aboard couldn’t believe the sight, which happened about 60km off shore in the Bremer Bay canyon.

Boat bosses say it's the first time such a dramatic attack has been recorded Picture: Machi Yoshida . (Supplied/Machi Yoshida )

“No one’s ever witnessed anything like it,” said Mr Cross.

“It’s like a lion taking down a wildebeest.

The dramatic attack was seen by 40 tourists on board the boat. Picture: Machi Yoshida (Supplied/Machi Yoshida )

“It happened so fast. People just couldn’t believe what’s unfolding.

“It can be a little bit brutal for some people but that’s nature and it’s going to happen.”

The pod of orcas converged quickly on the beached whale. Picture: Machi Yoshida (Supplied/Machi Yoshida )

The pod of, killer whales, also known as orcas, swam up to 50km an hour to converge on the Cuvier’s beaked whale, which can dive as deep as 3km.

As they attacked, a pool of blood started to spread through the ocean.

Birds circled for the remnants of the whale. (Supplied/Machi Yoshida )