"We are re-accommodating our customers on other flights," American Airlines spokeswoman Laura Nedbal said in a statement. "Safety is our highest priority and we apologize to our customers for the disruption to their travel plans."

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The co-pilot, who was not identified, was also given a Breathalyzer by local police. The tests showed he was over the legal limit for operating an aircraft.

He was released when his alcohol level dropped.

Michael Conway, airport spokesman, told the Detroit Free Press incidents like these are "extremely unusual."