Rare look at a secret weapon with four legs

Working dogs like those used domestically for anti-terror operations are also saving the lives of American soldiers on the battlefield. The best of those dogs, oftentimes Belgian Malinois breeds, are utilized by Special Operations troops to attack the enemy as well as sniff out bombs. Lara Logan gets a rare look into the secretive world of these special dogs -- some of whose capabilities are military secrets -- and their handlers on 60 Minutes on Sunday, April 21 at 7:00 p.m. ET/PT.

Mike Ritland trains Malinois to perform many roles -- some classified -- including attacking enemy troops. He demonstrates a training exercise to Logan at his ranch in Cooper, Texas, where he trains the dogs. In a scene captured by 60 Minutes cameras, a dog in training is sent after a running volunteer about 50 yards away. The dog, which can run over 30 mph, quickly overtakes the man, knocking him to the ground and biting his arm. The volunteer wears a heavy quilted suit to keep the dog's teeth from penetrating his flesh. But there's more for enemy soldiers or criminal suspects to worry about.

Logan asks how hard the dogs can bite. "Hard enough to break bones," says Ritland. Pointing to his wrists, he says "I had a dog bite me, right here like this, he only had his mouth on me for four or five seconds and broke my wrist."

Only extremely special dogs make it this far in training, says Ritland. They purposely put the dog under pressure and give them a choice to stay and fight or quit and run away. It's the ultimate test of what the dog will do if the target they attack tries to harm them. "The number-one thing I look for in a dog is that dog...decides I'm going to stay and fight you and I'm going to beat you. When you find that, it is a unicorn in that they almost don't exist," says Ritland.

The dogs have been used more and more since 9/11 and became extremely valuable in Afghanistan, where their skills give troops a mental comfort edge. "You know you've got one of the best trained, best equipped, best capable...working dogs out in front of you that has your back," says Ritland.

Unfortunately, the Taliban has begun to appreciate the dogs' advantage to U.S. troops and have targeted them. A reporter with a camera interviewed a Taliban commander for 60 Minutes who told him in a recent battle his force was ordered to open fire on the dogs before targeting the humans.

Told that some people would consider it animal cruelty to put the dogs in harm's way, Green Beret Chris Corbin, a Special Forces dog handler, tells Logan, "I could make [his dog] scared of it and make him not do his job and send soldiers to the same death. That's my answer to that."

When the dogs have served their tours with the military, they can end up on American streets to secure events and perform other police duties.