RIVERSIDE (CBSLA.com) — Riverside County supervisors Tuesday passed an ordinance requiring all pit bull dogs older than four months in unincorporated areas of the county to be sterilized.

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Officials unanimously approved the measure, which was sponsored by Riverside County Supervisor Jeff Stone, just after 1:30 p.m.

“Our goal after we pass the ordinance today is to pass it on to our 28 cities, so that we uniformly have some type of ordinance in place for the entire county,” Stone told KNX1070. “These dogs are being bred to be dangerous, to fight, to kill, and as a result we’ve seen a lot of terrible incidents, so it’s been a significant public safety problem for our residents.”

The supervisors voted 5-0 in September to move forward with the proposed ordinance, which is to “protect the public’s health and welfare from irresponsible owners of pit bulls by mitigating the over-population of unwanted pit bulls,” the Department of Animal Services said in a statement.

Under the ordinance, an animal can only be exempted from the law if its owner proves that the dog belongs to a registered breeder, is trained for law enforcement duties, serves as an “assistance dog” for a disabled person, is in training or licensed in another county or has been certified by a veterinarian as having a health defect that would be aggravated by sterilization.

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“I don’t think we’re trying to get rid of the breed. We’re allowing legitimate breeders to go ahead and continue to breed,” Stone said.

According to officials, 20 percent of dogs impounded and 30 percent of animals euthanized in Riverside County are pit bulls.

“People are raising them and finding out they are dangerous, they are sticking them in our pounds and our K-9 centers, and we are euthanizing them and we want to reduce the euthanasia in our dog kennels,” Stone added.

RELATED STORY: Riverside County To Consider Mandatory Sterilization For Pit Bulls In Unincorporated Areas

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