Israel has extended the detention without trial of Palestinian clown Mohammad Abu Sakha for another six months, his circus school said on Monday.

Abu Sakha, 24, was arrested on December 14 in the occupied West Bank, and held since January in administrative detention, the controversial measure under which Israel holds suspects without trial for periods of six months, renewable indefinitely.

"Administrative detention order extended (for) another six months. Our hearts are heavy," a statement from the Palestinian Circus School said.

The Shin Bet Israeli internal security agency confirmed his detention had been extended to December.

Rights group Amnesty International called Abu Sakha's detention "yet another shameful example of the Israeli authorities' abusive use of administrative detention".

"For decades, Israel has relied upon administrative detention, in many cases as an alternative to bringing Palestinians to trial, and used it to suppress peaceful dissent," it said in a statement.

"They must take urgent steps to end this cruel practice once and for all."

Shin Bet has accused Abu Sakha of being an active member of the leftist Popular Front for the Liberation of Palestine, which is considered a terrorist group by Israel and others because of its armed wing.

"Due to Abu Sakha's danger to the region's security, and lacking another alternative, Shin Bet recommended that the military command order his administrative detention," it said in a statement.

The Palestinian Performing Arts Network, representing artists and cultural institutions, earlier this year said it was "deeply concerned" by Abu Sakha's detention.

He has been part of the Palestinian Circus School in Bir Zeit in the occupied West Bank since 2008, first as a student and later as a clown and teacher.

Administrative detention is intended to allow authorities to hold suspects while continuing to gather evidence, with the aim of preventing further attacks in the meantime.

The system has been criticised by Palestinians, human rights groups and members of the international community.

Of more than 7,500 Palestinians currently in Israeli jails, around 700 are being held under administrative detention, Palestinian rights groups say.

Source: AFP