Cesar Millan, the self-taught dog behaviorist known to millions as the "Dog Whisperer," is under investigation for alleged animal cruelty, multiple media outlets reported late Thursday. 

A spokesman for the Los Angeles County of Animal Care and Control told The Wrap that officers had visited Millan's training facility in Santa Clarita, Calif., Thursday. It was not clear whether Millan had been interviewed about the allegation, but KNBC reported that Millan was out of town on a business trip. 

The station also reported that officials issued a 24-hour notice, requiring Millan to make contact with investigators. 

The investigation reportedly stems from a recent episode of Millan's show "Cesar 911," in which a live pig was used in a behavioral training session with a dog who had recently attacked two other pet pigs. The dog bit the pig's ear, drawing blood, before it could be subdued.

Los Angeles County Animal Control Deputy Director Danny Unbario told The Wrap that it had received a single complaint about the incident and described the case as "active."

Nat Geo WILD, which broadcasts "Cesar 911", said statement: "Cesar Millan has dedicated his life to helping dogs and to showing how even the most difficult 'problem dog' can be rescued and rehabilitated. 

"In a recent episode of the Nat Geo WILD series 'Cesar 911,' Cesar works with an aggressive French bulldog/terrier mix named Simon, who has a history of attacking other animals, including his owner’s pet pot-bellied pigs. A short clip from the episode was shared online and showed Simon chasing a pig and nipping its ear, causing the ear to bleed. The clip caused some concern for viewers who did not see or understand the full context of the encounter."

The network went on to say the pig "was tended to immediately afterward, healed quickly and showed no lasting signs of distress."

"Cesar 911" is Millan's second show featuring his behavioral work with dogs. "The Dog Whisperer" aired between 2004 and 2012 and shot the Mexico-born Millan to international fame. He has also written six books.

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