RAMALLAH, West Bank (AP) — A Palestinian circus artist who has been held without charges in Israel will ask an Israeli court this month to release him or reduce his sentence, his advocates said Thursday.

The announcement came a day after Israeli circus artists held a rally in support of their 24-year-colleague, Mohammed Abu Sakha. Wearing red noses, the performers juggled as they demonstrated outside an Israeli prison Wednesday.

Abu Sakha is a clown, juggler and tightrope walker who heads the Palestinian Circus School's program teaching circus arts to children with mental disabilities, according to the school in the West Bank.

He was on his way to work when he was arrested Dec. 14 by Israeli troops in the West Bank, said Hassan Safadi of the Adameer legal aid organization, which is representing him.

According to Israel's Shin Bet security service, Abu Sakha was arrested for "renewed activity" with the Popular Front for the Liberation of Palestine, a secular, left-leaning Palestinian faction that opposes peace with Israel. The group, which was involved in hijackings and other attacks in the 1970s, has scaled back its militant activities in recent years.

The circus artist is being held under administrative detention, a practice that can keep some prisoners in custody without charges for an indefinite time. He is being held for a six-month detention that could be renewed.

The Shin Bet also said Abu Sakha poses a "threat to the security of the region" and is being held without trial because the evidence against him is classified, among other reasons.

Israel says administrative detention is an important security tool necessary to stop militant attacks. International law permits detention without trial under extremely limited circumstances, but critics say Israel uses the measure on a large scale, denying detainees due process.

A court will hear Abu Sakha's appeal on March 21, Adameer said.