TRIPOLI - Libyan government forces air-raided the rebel-controlled eastern city of Ajdabiya Monday, killing at least one person and injuring 11, local reports said.

Ajdabiya, a stronghold set up by the rebels, was considered the first line of defense for their base camp in the eastern city of Benghazi. The rebel forces were gathering at the western entrance of the city to resist the attacks of government forces.

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Meanwhile rebels from nearby Brega, an eastern city the Libyan army claimed to have recaptured Sunday, also retreated to Ajdabiya in trucks equipped with anti-air weapons, eyewitnesses said.

Rebel Commander General Abdel Fattah Yunis, who resigned as Libyan leader Muammar Gaddafi's interior minister, said Sunday that Ajdabiya was "a vital city."

Eyewitnesses said dozens of Ajdabiya's civilians were leaving the city, heading west for Benghazi, 160 km west of Ajdabiya.

The Libyan army began their attacks on the rebel-held east on Sunday. Libyan Deputy Foreign Minister Khaled Kaim said in Tripoli Sunday that the state TV will broadcast footprints of the Libyan troops entering Brega.

The spokesman of the Libyan army also announced that government forces had recovered the western city of Zawiyah and the eastern cities of Ras Lanuf and Brega, adding the troops had completely vanquished the rebels in Brega.

Though Libya's oil exports have been hit hard by weeks of deadly clashes between pro-Gaddafi forces and opposition groups, the head of Libya's National Oil Corporation Shukri Ghanem said Monday that all oil fields in the country had remained intact.

Some armed groups looted oil companies' production bases and warehouses in costal cities such as Ras Lanuf and Brega, taking cars, heavy machinery and other supplies, and interrupting the facilities' normal operation, Ghanem said in a TV interview Monday.

The Libyan government is currently offering compensation to those oil companies to help restore their production as early as possible, he said, adding the National Oil Corporation is calling on oil workers to immediately return to work once the situation in the country stabilizes.

Ghanem also said the Zawiyah refinery in the west of Libya had restored 60 percent of its capacity.

In addition to Zawiyah, Ras Lanuf and Brega, government forces have recently retaken the eastern city of Bin Jawad. Ras Lanuf and Brega are Libya's important oil exporting ports and petrochemical bases.