American Airlines, which owns and operates American Eagle, and the Transportation Security Administration said an officer from the agency either stepped on or grabbed probes mounted on the fuselage of nine American Eagle planes while conducting routine checks to ensure the planes hadn't been tampered with overnight at O'Hare Airport, the Chicago Tribune reported Wednesday.

The airline said 40 flights were delayed Tuesday while the planes were checked for damage.

"There is a sign that clearly says, 'Don't step,'" American spokeswoman Mary Frances Fagan said of the probes.

Fagan said no damage was found on any of the planes, but each of the aircraft took up to two hours to thoroughly inspect.

TSA spokesman Elio Montenegro said inspectors will be retrained to prevent future problems.