Clashes have intensified in Libya’s eastern oil port of Brega, as anti-government fighters fought to expand their control beyond the city’s residential sectors.

Opposition forces Tuesday said loyalist troops in trucks disguised with rebel flags had shelled their positions, killing eight insurgents and wounding dozens more.

But a rebel spokesman also said radio intercepts from Brega suggest forces loyal to leader Moammar Gadhafi are low on food and weapons. He said many pro-government troops have retreated to the west, leaving only a reduced force to defend the strategic city.

Still, opposition commanders played down their chances of swiftly capturing Brega and its petrochemical complex. They say hundreds of land mines planted by Mr. Gadhafi’s forces continue to delay their advance.

Rebel fighters also said loyalist troops have set fire to ditches filled with flammable liquids, creating black smoke that covers their movements from NATO aircraft.

They said the alliance has recently stepped up airstrikes on government military convoys near Brega.

The toll in five days of clashes has risen to at least 32 opposition fighters killed and nearly 300 wounded. The Los Angeles Times quotes a government spokesman as saying 30 loyalist fighters have been killed in the fight for Brega.

In an audio address to a pro-government rally in the western town of al-Aziziya Tuesday, Mr. Gadhafi vowed again that he will not bow to the pressure of NATO or the rebellion against him. The Libyan strongman also made a rare reference to the fuel shortages caused by Tripoli’s international isolation that have made life hard in government-controlled areas.

In a separate development, reports said Libya’s foreign minister will meet his Russian counterpart in Moscow Wednesday, in a visit requested by the Libyan government. Russia has been heavily involved in attempts to mediate between the rebels – who control much of eastern Libya – and Mr. Gadhafi’s inner circle.

Opposition forces have been fighting since February to end the Libyan leader’s four decades of autocratic rule. NATO warplanes have been helping the rebels by bombing pro-Gadhafi forces under a U.N. mandate to prevent government attacks on civilians.

In a separate development, the International Committee of the Red Cross said medical workers are struggling to handle a flood of casualties in the western Nafusa mountain region, where rebels have gained control of several towns. The ICRC said medical facilities there have been cut off from Libya’s health ministry.