Forces fighting to oust the Libyan leader Col Muammar Gaddafi have seized the city of Zawiya, 50km (30 miles) west of the capital, Tripoli.
The Libyan government took journalists to Zawiya on Sunday morning.
But instead of a show of government force, reporters saw opposition fighters manning the barricades in the city centre and flying their flag.
The UN Security Council voted unanimously on Saturday to impose sanctions on Col Gaddafi’s regime.
Eastern Libya has fallen to the uprising, which began on 16 February in the wake of revolutions which toppled the long-serving leaders of neighbouring Tunisia and Egypt.