IN THIS disturbing video, a huge saltwater croc can be seen calmly swimming along with a pet dog held firmly in its jaws.

The video was posted to the Bogged group on Facebook, and quickly racked up more than half a million views in only a few hours.

This large saltwater crocodile can be seen swimming next to a dock with a pet dog in its mouth. Courtesy: Facebook/Bogged Source: Supplied

The crocodile can be seen calmly swimming along the side of a dock holding the dead pet dog.

The large black dog has a red collar and is clearly a pet.

The administrator of the Bogged group was sent the video, but it is unclear where it was taken.

It appears to be somewhere in South America.