ROMULUS, Mich. (AP) — Authorities say an airline passenger was arrested in Michigan after being found with a knife inside the bottom lining of a shoe in his carry-on luggage.

The Transportation Security Administration says the knife was found Sunday during security screening at Detroit Metropolitan Airport in Romulus.

The TSA says the knife should have been placed in checked luggage.

Airport spokesman Brian Lassa line (LASS’-uh-leen) says the incident happened about 7:30 a.m. at the airport’s North Terminal.

He says airport police arrested and then released the man while the Wayne County prosecutor’s office decides on charges.

Lassaline says finding the knife in the man’s carry-on luggage shows “the security screening process working as it should” and says the incident didn’t present a threat to public safety.

Authorities haven’t released the man’s name.

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