Probably a very large lizard, in the
monitor lizard or komodo dragon family. They're carnivorous, aggressive, grow very large (up to 10 feet or more), can sit or stand upright for small periods of time, and according to one commentator on the youtube site the claw marks are similar to ones he's seen left by a monitor lizard.
There are probably some varieties that are indigenous to the area, or perhaps someone across the border in Mexico had a pet that escaped.