A man who was fishing in the Adelaide River was taken by a crocodile, and the man's wife witnessed the frightful assault, Northern Territory Police confirmed.

"He was there with his wife and he was fishing on the water's edge," NT Police Superintendent Jo Foley told ABC News. The wife "left the scene because she saw this happen," he added. Other reports said the wife ran to call for help.

News.com.au has photos of the scene in its report, which mentioned police began their search for the victim at 8:30 in the evening. Police found what is presumed to be human remains at 9:30 p.m. after "several gunshots" were fired.

News.com.au said the wife was treated for shock when the ambulance arrived. The man was reported to be 57 years old.

"A 4-4.5 metre Croc has been recovered with what are believed to be human remains at Adelaide River," Nine News Darwin updated its followers on Facebook with this photo.

The man was on the water's edge off the Arnhem Highway, but got in water when he encountered some trouble with his fishing equipment, Nine reported.

This is the fourth crocodile attack that ABC has documented since January this year, when a crocodile took and killed a 12-year-old boy in Northern Territory's Kakadu.

"Adelaide River is a well known crocodile hot-spot," ABC reported, adding that the river is a destination for tourists who pay for cruises to see the crocodiles.

Earlier this month, NTNews reported photos of a crocodile which took a shark, also in the Adelaide River. The shark is known as Brutus, who is apparently distinct for his missing limb. Brutus the crocodile is over 80 years old, according to NT News.

According to the Crocodile Specialist Group, there are four reasons why "crodilians" take humans: One, the crocodiles, particularly the large ones, see humans as prey. Two, the crocodiles are protecting their territory. Three, the crocodiles attack to protect their young. Four, some humans are bitten by mistake (e.g. attack is targeted at some animals near or accompanied by humans).

In Australia, CSG reported, 25 percent of the attacks by a saltwater crocodile are fatal.

In a related report, a video showing a man being chased by a crocodile -- reportedly in Mexico -- has gone viral on YouTube and other social media networks.

Viral Video: Man Swims For Life As Crocodile Chases After Him