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 today 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.