Israel has extended the detention without trial of Palestinian clown Mohammad Abu Sakha for another six months, his circus school said 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 can hold 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.
Amnesty International has called for Abu Sakha's release.
Shin Bet has accused him 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 due to 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" over the detention of Abu Sakha.
Abu Sakha 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.
More than 7,500 Palestinians are currently in Israeli jails, of whom around 700 are held under administrative detention, according to Palestinian rights groups.