Libyan rebels on Sunday retreated from another key town under heavy shelling from government forces as Moamer Kadhafi loyalists swept closer towards the main opposition-held city of Benghazi.
But following the fall of Brega, the commander of the vastly outgunned rebels, Kadhafi's former interior minister, vowed to defend the next town in the path of Kadhafi's forces, Ajdabiya.
A lightning counter-offensive over the past week has pushed the rebels out of Mediterranean coastal towns, allowing the regime to wrest back the momentum against the month-long uprising against Kadhafi's four-decade grip on power.
Kadhafi's forces are "marching to cleanse the country" of insurgents, Libyan army spokesman Colonel Milad Hussein told reporters in Tripoli.
"Our raids are forcing the terrorists to flee. We have liberated Zawiyah, Uqayla, Ras Lanuf and Brega, and the army is advancing to liberate the rest of the regions."