NEWHALL (CBSLA.com) – The FBI is investigating the circumstances surrounding an off-duty agent who, according to the Los Angeles County Sheriff’s Department, shot and killed a pit bull who attacked his German shepherd on Friday in the Santa Clarita area.

The agent was walking his dog on a leash when the unleashed pit bull attacked his dog, sheriff’s Lt. Chuck Becerra said. There was no crime suspected in the shooting, but an investigation is customary whenever an agent uses his or her gun.

The shooting was reported at 5:38 a.m. Friday in the area of Piazza Di Sarro and Sierra Highway, Becerra said.

The agent tried to pull his dog away, but the attack continued so he pulled out his gun and fired one shot at the pit bull, killing it, he said.

The pit bull was walking with its owner during the attack, Becerra said. Animal Control officers came and took the deceased dog away.

Laura Eimiller, an FBI spokeswoman, confirmed to CBS2 that the agency always opens an investigation when an agent discharges their firearm.

The attack in Newhall came two days after an unrelated incident in which a man was injured and his small dog killed in the Skid Row section of downtown Los Angeles by three pit bulls who were eventually shot by a police officer.

The owner of the pit bulls cooperated with investigators and was not arrested for the attack that occurred about 8:30 a.m. Wednesday in the 500 block of Stanford Avenue, said Officer Sal Ramirez of the LAPD’s Media Relations Section.

An officer shot three pit bulls, two of them fatally, Ramirez said. The third animal survived and was taken for medical treatment by Animal Control officers.

Cell phone video taken during the attack showed officers using batons in a vain attempt to stop the mauling.

An area business owner told reporters the pit bulls lived on the grounds of a neighboring business, were allowed to briefly run free each morning after being let out of their enclosures, and would typically obey the commands of a man who owns or tends to the dogs.

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