(CNN)A co-pilot for American Airlines was detained at Detroit Metropolitan Airport Saturday morning on suspicion of being drunk, an airport spokesman said.
The co-pilot was taken into custody after allegedly failing a Breathalyzer test administered by airport police, according to airport spokesman Michael Conway.
As a result of the incident, American Airlines canceled Flight 736 from Detroit to Philadelphia on Saturday.
“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.”
Airport police were called to the North Terminal in the early morning hours in response to a report of a pilot who was “exhibiting signs of being drunk,” Conway said.
The co-pilot was administered a more precise sobriety test at a local police department. Both tests showed he was over the legal limit for operating an aircraft, airport police said.
Authorities will not name the co-pilot pending possible charges, but said he was born in 1965 and is a resident of Pennsylvania.
He was later released from custody after his alcohol level dropped, Conway said.
Airport police are now developing a case to present to the local prosecutor’s office, Conway said, noting that these kinds of incidents are “extremely rare.”