Updated

Egyptian security officials say 242 supporters of the Muslim Brotherhood have been referred to new trials, the latest in a series of mass tribunals against backers of the ousted Islamist president over protests and violence.

Thousands have been arrested in a crackdown on Mohammed Morsi's backers since his ouster in July. Recently authorities have announced a string of trials of low-level Brotherhood members, each with dozens of defendants.

In the latest cases, the officials said Thursday that 170 Islamists in the southern city of Assiut were charged with storming and burning government installations.

Another 72 in Beheira province, northwest of Cairo, will be tried on charges of attempted murder, illegal protests and acquisition of firearms.

The officials spoke on condition of anonymity because they were not authorized to brief reporters.