Terrifying moment scuba diver is speared by swordfish (video)

A scuba diver is lucky to be alive after he was attacked by a swordfish in an unprovoked underwater attack.

In footage filmed by a fellow diver, the man is seen walking along the ocean floor off the coast of Brazil when the swordfish appears from nowhere and charges at him.

The five-foot fish spears the diver's oxygen equipment and impales the tank. It is then seen thrashing around as it tries to free itself.

With the fish lodged in his scuba gear, the diver is forced to climb back up his rope towards the boat.

The video has been views more than 1.7 million times since it was posted online last week.

Last year, a man died after being speared by a swordfish in Hawaii.

Randy Llanes, 47, dived into the water in Honokohau Harbour, Kailua-Kona, after spotting the 3ft-long fish.

He shot it with his spear gun but as the fish started thrashing around it impaled him in the upper chest with its bill, boating and ocean recreation officials said.

According to NBC News, fishermen pulled Llanes out of the after the accident and attempted CPR but he was declared dead at a nearby hospital.

Swordfish are normally found in deep water but sometimes during the day they can swim near the surface. Experts say it is very unusual for them to be in shallow water.