When in danger, you need to use anything you can to protect yourself.

In a story of true heroics, a 72-year-old man has used spanners and spark plugs to defend himself from an onslaught of crocodiles in Australia's top end in a three-hour ordeal on Tuesday.

The unnamed man and a 75-year-old friend, Noel Ramage, from Bendigo, Victoria were trying to catch crabs in Saltwater Arm, close to Darwin in the Northern Territory, when disaster struck.

A crocodile deliberately knocked their boat over and threw them into the water as they were bringing pots into their three-metre "tinny" boat, according to ABC News.

Image: Getty Images

Ramage was trapped under the capsized boat, which resulted in his drowning. The 72-year-old surviving man managed to get on top of the boat and used whatever he could find to fend off the crocodiles as he tried to push the boat to safety.

"He was using spanners and spark plugs to hold them at bay," Ian Badham, director of CareFlight told ABC News. Badham also revealed the man had used a spanner to hit a crocodile over the head.

The man finally managed to get the boat to the mangroves, but became stranded in the mud as his three-hour encounter with the beasts continued, according to a statement by CareFlight, a medical rescue charity. It was only when the tide came in he could get enough buoyancy to pull his boat into a safer position.

Eventually, three professional crabbers heard his shouts and rescued him. They transported the brave man to a boat ramp so they could get enough phone signal to call for help.

A doctor and nurse from CareFlight were sent to retrieve the man, who was treated for severe shock and flown to Darwin for further treatment, which included dehydration and exposure, according to the ABC. He was released from hospital overnight.

Northern Territory's government estimates there are between 100,000 to 200,000 saltwater crocodiles in its waters, with the numbers rapidly rising after they were listed as a protected species in 1971. Despite news of frequent attacks, not many people have to take on the wild reptiles for a life-or-death battle.

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