HOUSTON (AP) — Nigerian aviation officials say a preliminary review of security video shows no evidence that a U.S. air marshal was stabbed with a syringe at the airport in Lagos (LAY’-gohs).

The Federal Airports Authority of Nigeria reported Wednesday that its officials and U.S. Embassy personnel have reviewed the security footage. The video shows the U.S. air marshal’s movement on Sunday.

The air marshal says he was attacked before boarding a United Airlines flight. He was taken to a hospital after landing in Houston at Bush Intercontinental Airport on Monday.

The FBI declined comment Wednesday. But the agency has said preliminary tests on the syringe, which the air marshal was able to get after the assault, didn’t show any deadly pathogens.

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