The San Diego County Sheriff's Department bomb unit detonated a package found at the back door of a Home Savings of America office in Ramona only to find it had contained four kittens. A sheriff's spokeswoman said three of the kittens were killed by the blast and the fourth was taken to a veterinarian. The spokeswoman said the package was X-rayed and found to contain a living creature, but the type could not be determined. Because of a related incident in Ramona in which a rattlesnake was left in a box on a woman's driveway, an explosive charge was put on the box and it was detonated. After being treated by the vet, the surviving kitten was taken home by bomb squad member Sgt. Conrad Grayson. A sheriff's spokesman said Grayson felt terrible about his role in the incident. "He loves cats," the spokesman said. "The cat will be OK. He named it Lucky."