Ajdabiya, Libya (AP) - Rebel fighters claimed NATO airstrikes blasted their forces Thursday in another apparent mistake that sharply escalated anger about coordination with the military alliance in efforts to cripple Libyan forces. At least two rebels were killed and more than a dozen injured, a doctor said.
The attack -- near the front lines outside the eastern oil port of Brega -- would be the second accidental NATO strike against rebel forces in less than a week and brought cries of outrage from fighters struggling against Moammar Gadhafi's larger and more experienced military.
"Down, down with NATO," shouted one fighter as dozens of rebel vehicles raced eastward from the front toward the rebel-held city of Ajbadiya.
Later, hundreds of cars poured out of Ajbadiya toward the de facto rebel capital Benghazi amid fears that pro-Gadhafi forces could use the disarray among rebel units to advance.
In Brussels, a NATO official said the alliance will look into the latest rebel claims but he had no immediate information. The officials spoke on condition of anonymity under standing regulations. NATO also dismissed Libyan claims that British warplanes struck the country's largest oil field, saying the attacks were carried out by government forces.
NATO last week took control over the international airstrikes that began March 19 as a U.S.-led mission. The airstrikes thwarted Gadhafi's efforts to crush the rebellion in the North African nation he has ruled for more than four decades, but the rebels remain outnumbered and outgunned and have had difficulty pushing into government-held territory even with air support.
A rebel commander, Ayman Abdul-Karim, said he saw airstrikes hit tanks and a rebel convoy, which included a passenger bus carrying fighters toward Brega. He and other rebels described dozens killed or wounded, but a precise casualty toll was not immediately known.
A doctor at Ajbadiya Hospital, Hakim al-Abeidi, said at least two people were killed and 16 injured, some with serious burns. Other rebel leaders said other casualties were left in the field in the chaos to flee the area.
The small medical facility was overwhelmed. One rebel sat in a hallway, wrapping gauze around his injured leg.
On Saturday, a NATO airstrike killed 13 rebel fighters in eastern Libya. An opposition spokesman described it as an "unfortunate accident" in the shifting battles and pledged support for the international air campaign to weaken Gadhafi's military power.
But rebel discontent with NATO appears to be growing. Opposition commanders have complained in recent days that the airstrikes were coming too slowly and lacking the precision to give the rebels a clear edge. NATO officials say that the pro-Gadhafi troops have blended into civilian areas in efforts to frustrate the alliances bombing runs.
The rebel commander Adbul-Karim said the tops of rebel vehicles were marked with yellow under advice by NATO to identify the opposition forces. But rebels use tanks and other vehicles commandeered from the Libyan army -- potentially making their convoys appear similar to pro-government units from the air.
The attack occurred about 18 miles (30 kilometers) from Brega, where rebel forces have struggled to break through government lines, he said.
Rebels also have turned to the oil fields under their control as a source of money for weapons and supplies. The Liberian-flagged tanker Equator, which can transport up to 1 million barrels of oil, left the eastern port of Tobruk en route to Singapore on Wednesday, oil and shipping officials said.
But sustained attacks on the main rebel-held oil fields have crippled production. Libya claimed British jets waged the bombings. NATO, however, dismissed the accusations and blamed Gadhafi's forces.
"We are aware that pro-Gadhafi forces have attacked this area in recent days," said Canadian Lt. Gen. Charles Bouchard, who commands the allied operation. "To try and blame it on NATO shows how desperate this regime is."
Two explosions were heard Thursday in Libya's capital Tripoli, but the cause of the blasts was not immediately known.
In London, officials said an international group overseeing political initiatives on Libya is scheduled to hold its first meeting next Wednesday in Qatar, one of the few Arab nations contributing aircraft to the NATO mission. The so-called "contact group" includes European nations, the United States, allies from the Middle East and international organizations.
Associated Press writer Hadeel al-Shalchi in Tripoli, Libya, and Slobodan Lekic in Brussels contributed to this report.