TRIPOLI, Libya (AP) — Libya’s military banned flights Saturday over the eastern city of Benghazi, a day after troops loyal to a rogue general attacked Islamist militias in violence that killed 51 people, authorities and medical officials said.

The North African nation’s weak central government already described the offensive Friday by Gen. Khalifa Hifter, which included military air support, as tantamount to a “coup.” And as militiamen reported a separate helicopter attack on one of their bases Saturday, the violence again showed how precarious government control remains after the 2011 civil war that toppled dictator Moammar Gadhafi.