It was a case of shark eat shark at an aquarium in South Korea earlier this week following a 'turf war'.

Visitors to the COEX aquarium in Seoul witnessed an eight-year-old female sand tiger shark eat her male companion over the course of almost an entire day.

Shark experts say they are territorial creatures and she devoured her tank mate because he kept bumping in to her.

It took the female 21 hours to eat the five-year-old male, starting with his head.

Oh Tae-youp, manager at the aquarium, told Reuters, "I think the shark swallowed the whole body, because they usually eat it all when they bite the head part".

The tail is expected to remain in the shark's mouth for several days. The devoured shark will later be regurgitated as the larger shark - which is around 2.2 meters (7.22 ft) long - is unable to digest it.

Video footage of the incident shows the female shark circling the tank with the smaller shark hanging out of her mouth: