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Cindy McCain believed she had helped thwart a child trafficking case when she saw a toddler with "a woman of a different ethnicity" at Phoenix's airport. But police said that's not what happened.

McCain, who sits on the advisory council of the McCain Institute founded by her late husband, Sen. John McCain, made the claim Monday while talking about sex trafficking during the Super Bowl on the "Mac and Gaydos" radio show on KTAR News 92.3 FM.

"If you see something, say something. That very thing happened to me at the Phoenix airport last Friday," McCain said, referring to Phoenix Sky Harbor International Airport.

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McCain said she was coming home from a trip when she "spotted — it looked odd — it was a woman of a different ethnicity than the child, this little toddler she had. Something didn't click with me."

"I went over to the police, and I told them what I thought, and they went over and they questioned her," McCain said. "And by God, she was trafficking that kid."

"She was waiting for the guy who bought the child to get off an airplane," she added.

But a Phoenix Police spokeswoman told NBC News that while they did perform a welfare check at Sky Harbor airport at McCain's request, "officers determined there was no evidence of criminal conduct or child endangerment."

McCain has not explained what caused her to believe she had caught a trafficking case, but wrote on Twitter on Wednesday: "At Phoenix Sky Harbor, I reported an incident that I thought was trafficking. I commend the police officers for their diligence. I apologize if anything else I have said on this matter distracts from 'if you see something, say something.'"

McCain co-chairs the Arizona Human Trafficking Council and largely works to combat human trafficking.

The McCains adopted one of their four children, Bridget McCain, from Bangladesh.