From ABC Channel 7 in Denver, Colorado, a story about two pit bulls that were shot by animal control officers attempting to rescue a cat owner from the dogs. 

The owner of these dogs apparently allowed the dogs to escape custody; the dogs were running around loose, the officers were called and were attacked.  They made it back to their vehicle, called for backup, then saw the dogs attack a cat.  The cat owner tried to save the cat, the dogs then went after the owner, and the control officers first taisered the dogs, then shot them to save the owner of the cat.

Colorado has had a string of pit bull attacks in the past couple of years, the worst of which caused the death of a woman in November 2003.  The owner of the pit bulls in that case has been sentenced to six years in prison, and has begun serving her term.