A whale shark was brought to the Karachi Fish Harbour early Thursday to be auctioned off to bidders, but harbour authorities said they will be arresting the fishermen who hauled it in because the fish is a rarity in Pakistani waters and not supposed to be hunted.

Weighing about three tons and measuring 16-17 feet in length and 4ft wide, the shark was reportedly 'caught' in the proximity of Indian waters after it reportedly injured itself in a collision with a fishing boat and then got entangled in fishing nets and lost its life.

The fishermen involved in the incident took the whale to Ibrahim Hyderi, a settlement off the coast of Karachi. From Ibrahim Hyderi, the whale was transported to the fishing harbour.

The fishermen have maintained that the fishing authority does not have the powers to impose a fine on them, adding that any such measure would equate to 'asking for a bribe'.

The only usable substance from this species of shark is a fatty oil that is used by fishermen for layering their boats with a protective coating.

Back in 2010, another whale shark had been dragged to Hawksbay shore by fishermen whose nets the enormous fish had found itself entangled in.