Visitors to an aquarium in South Korea, on Thursday witnessed a gruesome and brutal side of Mother Nature as they watched a shark devour another smaller shark.

Video footage shows the biggest shark in Seoul's COEX Aquarium eating her tank mate in what was likely a "turf war."

In the video, an eight-year-old female sand tiger shark that measured at 7-foot, 3-inch long is seen slowly eating a smaller five-year-old male banded hound shark that was about 1.2. meters in length. This marked the first time that such an incident took place in Seoul's COEX Aquarium.

The sands shark took her first bite of the smaller shark sometime Thursday evening. The female was then filmed by bystanders swimming with the body of her prey hanging out her mouth.

However, it took her 21 hours to finish devouring the small shark. By the next day, all that remained of the male shark was the tip of his tail, which was still hanging out of the tiger shark's mouth.

"Sharks have their own territory. However, sometimes when they bump against each other, they bite out of astonishment," the aquarium's PR manager, Oh Tae-youp told Reuters. "I think the shark swallowed the whole body, because they usually eat it all when they bite the head part."

According to workers at the aquarium, the deceased shark's tail will most likely remain hanging there for up to five days. Because the female shark is unable to fully digest her conquest, she will eventually regurgitate it up about a week later.

Back in November, one unlucky woman was attacked by a shark the very first time that she ever stepped into the ocean.

The attack occurred when Jill Kruse of Colorado Springs, Colorado, was vacationing in Florida at Cocoa Beach. Within 10 minutes of getting into the ocean, she felt a shark bite into her leg.

"I was excited but also nervous at the same time, almost like I knew something was going to go wrong," the 28-year-old told KDVR Fox 31.

Fortunately, she survived the attack.

Watch video of the shark below.