FUQUAY-VARINA, N.C. (WTVD) -- An off-duty Cary police officer shot a dog after it attacked his sister and her dog on the officer's property, authorities say.It happened shortly after 7 a.m. Wednesday in the 1700 block of McLaurin Lane in Fuquay-Varina.A neighbor's pit bull mix was loose when it ran onto the Cary officer's property and attacked, according to the Fuquay-Varina Police Department.The officer shot and killed the neighbor's dog after he heard his sister screaming.The woman and her leashed dog were treated at the scene for injuries and referred for further treatment.Wake County Animal Control was called in to assist Fuquay-Varina Police with the investigation. Cary Police were also notified of the incident.Fuquay-Varina Police noted that it's unlawful for an animal to run loose off the owner's property. Any animal not on its owner's residence must be leashed and controlled.