Abu Sakha has been arrested by Isreali military on Monday 14 of December at the Zaatara Checkpoint while crossing by taxi from his home in Jenin to his work in Ramallah to assist a music concert. On Monday December 22, he was sentenced by a military court to administrative detention, without any charges presented to him. Administrative detention, often condemmned by the UN Human Rights Office and the Human Rights Committee, allows the Israeli military to hold prisoners indefinitely on secret information without charging them or allowing them to stand trial. The detention order is currently under review. A global petition for Mohammed has been made on  Avaaz.
update 19.01.16: Amnesty International has published a multilanguage report

Source and updates: Palestinian Circus School