They fired 4 bullets at Rex, but he did not loosen his grip, and continued to fight

Xavier Mercado ignored the persistent knock on his front door. However, soon after, a 16-year-old boy saw two strange men wandering around his house! It was at this moment that Rex, the teenager’s German Shepherd, jumped out from under his feet and ran down.

The dog raced straight to the intruders – and what she did next saved Javier’s life.