A senior U.S. military official said Tuesday the U.S. armed forces is investigating allegations that its troops assaulted and detained a Japanese journalist who was covering a raid on civilian houses in Baghdad.

Japan Press reporter Kazutaka Sato, 47, was beaten by U.S. soldiers while photographing civilian damage caused by a U.S. raid in Baghdad's Mansur district Sunday, according to Sato's colleague, Mika Yamamoto, who was on the scene.

Yamamoto said U.S. soldiers threw Sato to the ground, tied his hands and detained him for an hour.

According to Yamamoto, the soldiers beat up Sato after urging him not to shoot the scene and they did not give any reason why they were banning their reporting.

Yamamoto claimed the U.S. soldiers may have been trying to hide the bodies of civilians killed in the operation.

The senior U.S. military official said he personally believes the troops did not detain Sato, but authorities are currently investigating.