I'm glad you caught them. Things could have been much worse!

My sister has seven Siberian huskies. She had to put electric wire around the top of her six foot fence. Judging from her experiences, if a husky wants out, it is going to get over the fence. The electric wire stops hers, though. And it doesn't do any damage to them, it's just a little shock. My sister and I both touched the wire to make sure before she used it with the dogs. It is quite an unpleasant sensation, that's for sure, but its not agonizing or anything. Better a little shock once or twice than hit by a car.