A fisherman freed an endangered right whale that was caught in heavy fishing lines.

After noticing a whale tangled in thick ropes and struggling to get out, Adrian Colaprete jumped into the water with a mission to liberate the trapped creature, the Daily Mail reported.

The right whale was the last thing he was expecting to see on a casual fishing trip 50 miles off the coast of Virginia beach.

"You could see the lines wrapped around his pectoral fins," said Colaprete. "It was actually dugged into his skin a little bit," Colaprete told WVEC News.

Colaprete dove in armed with a large knife and video camera.

"When the whale slowed down, I had my knife ready, I said I'm going to take the opportunity, swam down there made one single cut," Colaprete said.

"I told him to be careful, it's a very large animal, we don't want whatever's entangled, if it was entangled, to get around him," Pat Foster, another member of the fishing trip who was the first to spot the whale, said.

 "It just felt right," the brave fisherman told PilotOnline, via the Daily Mail. "Being part of it was something bigger than me."

Colparetes said he couldn't see the whale when he first jumped into the water. When he finally was able to see it he described the large creature as "almost like a submarine coming at me."

"It was kind of scary at first," he said.

After the rope was cut, Colaprese was able to get one last shot of the whale's tail before it swam deep into the ocean.

Whale sightings off the Virginia coast are not out of the ordinary, but spotting a right whale is more unusual.

The ocean-dwelling mammals have been endangered since the 19th century, when they were almost hunted to extinction.

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