For one American Jewish teenager, this year's Jerusalem Day earlier this month turned out to be an event not to remember, as he was detained for two days on suspicion of attacking and biting a police officer.

"Lucas," a 19 year-old from Philadelphia, cut a rather different figure in the Jerusalem Day flag parade in the capital. Like many participants in the event, he wore a skullcap on his head; unlike the others, however, a Palestinian flag and a keffiyeh were also part of his outfit.

The youth, who arrived in Israel as part of a trip arranged by a Jewish-Christian group, claims he was attacked by a policeman during the celebrations.

The parade turned ugly this year when a small group of participants walked through East Jerusalem, and the Old City's Muslim Quarter, chanting "death to Arabs." Lucas, with a few comrades, stood opposite these demonstrators, and shouted out slogans in support of ending Israel's occupation of the territories. He says that dozens of Palestinians gathered behind him, and formed a spontaneous protest.

In a videotape, Lucas can be seen refusing to give policemen his passport, after he was apparently identified as the leader of the protest. After a few minutes, in the clip, a police officer is seen dragging Lucas forcibly into a police car.

"Israel is occupying the Palestinian people in my name, in the name of world Jewry," Lucas, clutching his American passport, tells the camera. "And I myself, an American Jew, is here to say that is completely unjustified and ethically reprehensible.

Open gallery view Jewish American identified as Lucas Koerner. Credit: YouTube

"And we, world Jewry and all people of the world, will not stop until this occupation ends and until the Palestinian people have their right - the right of return, the right to live without occupation, and equal rights within Israel. That is why we are here."

Israel Police claims the young man attacked and bit an officer - however, the video does not show Lucas provoking any officers. It shows a group of policemen forcing him to the ground and handcuffing him; as a result, he required medical treatment afterward.

For his part, Lucas adamantly denies that he attacked a police officer.

"I didn't bite anyone," he says. "The police officer showed me his cuts [later], but they were caused by a sharp instrument, and there weren't any bite marks."

Lucas was held in detention for two days. The Jerusalem Magistrate's Court denied a police request to extend his remand; at the advice of his lawyer and family, the youth left the country after being released.

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