The U.S. State Department confirmed Saturday a Tampa, Fla., youth of Palestinian descent is being held by Israeli authorities in Jerusalem.

The department said an official from the U.S. Consulate in Jerusalem visited Tariq Khdeir, 15, who was arrested during rioting after the funeral Friday of his cousin, Muhammad Abu Khdeir, 16, who was burned to death in alleged revenge for the kidnap-killing of three Jewish teenagers -- Gil-Ad Shaer, Naftali Fraenkel, and Eyal Yifrah -- whose bodies were found Monday, as reported by the Jerusalem Post.

“We are profoundly troubled by reports that he was severely beaten while in police custody and strongly condemn any excessive use of force,” the State Department said in a statement. “We are calling for a speedy, transparent and credible investigation and full accountability for any excessive use of force. We reiterate our grave concern about the increasing violent incidents, and call on all sides to take steps to restore calm and prevent harm to innocents.”

The Israeli Justice Ministry late Saturday said an investigation of Khdeir’s alleged beating by Israeli security forces had been opened, the Jerusalem Post reported. A video on YouTube of the alleged beating went viral.

Israeli police spokesman Micky Rosenfeld said the boy allegedly attacked security officers during the rioting, the New York Times reported, but the youth’s father, Salah Abu Khdeir, told the Associated Press his son was not involved. Rosenfeld said the video of the alleged beating had been edited, the Times reported.

The unrest spread into Arab towns inside Israel Saturday as rocket fire from Gaza into Israel also increased, Agence France-Presse reported.