ONTARIO (CBSLA.com) — A security alert was reported at Ontario Airport Friday evening, according to authorities.

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Hundreds of passengers were stranded and planes were grounded.

CBS2/KCAL9’s Juan Fernandez reported from the airport where he said passengers had a very rough night.

The airport’s Terminal 4 had to be cleared out, passengers have to be taken off planes they already boarded and re-screened.

A passenger reportedly gave TSA agents the slip — unintentionally. The incident occurred between 6:20 and 6:35 p.m. but that 15 minutes ended up costing passengers another hour in waiting.

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Fernandez spoke to a passenger named George (he didn’t want to give his last name) who was standing behind the male passenger when the incident occurred. “I was going through security this TSA agent turned around and he said, ‘Hey, where did that guy go'”?

George said the man was flagged for a secondary screening but rather than wait, he walked passed another group of TSA agents and went into the terminal.

Lindsay Frasier had already cleared security. “We were put on hold and told if we had gone through, we would have to go through again even if they already went through security. So, back in line.”

Passenger Lisa Bloom was already seated and headed to Sacramento when she said agents came on her plane and told everyone to deplane. “They asked if any male passengers had gone through security between 6:20 and 6:35?…and no one volunteered, so they emptied out the plane.”

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Fernandez reported all passengers were eventually accounted for and agents chalked up the man breaching security as a simple miscommunication.