BENGHAZI, Libya (AP) - A NATO airstrike intended to thwart Moammar Gadhafi's forces killed 13 rebel fighters in eastern Libya instead, the opposition said Saturday, but they described it as an "unfortunate accident" and stressed it did not diminish their support for the international air campaign.
The rebels' response to the attack - blaming it on a mistake within their ranks - highlighted their heavy dependence on the international air campaign as they face the superior military power of the longtime Libyan leader. The misfire also showed the challenges the coalition faces in identifying targets without coordination with forces on the ground.
"As regrettable as it may be, we understand that we might have to give up lives for the greater good. We have to look at the bigger picture," opposition spokesman Mustafa Gheriani said. "This is a war and the lines are so fluid going back and forth, so it's natural that mistakes will happen."
The slain fighters were hit Friday night as they moved forward, attempting to take back the oil city of Brega, while airstrikes were in progress. Seven fighters were injured. Another opposition spokesman, Abdel-Hafidh Ghoga, said it was an example of the lack of coordination in the ranks that has proven a key obstacle to victory over the more organized Libyan military.
Rebels without training - sometimes even without weapons - have rushed in and out of fighting in a free-for-all for more than six weeks, repeatedly getting trounced by Gadhafi's more heavily armed forces. But ex-military officers who have joined the rebel side have stepped up training efforts and taken a greater role in the fight.
"This unfortunate accident was a mistake that was caused by the rebels' advance during the coalition's attack," Ghoga said. "Now the military leadership that has been organized more effectively recently is working on preventing the recurrence of these accidents."
Rebels in the field had previously said some of their comrades were killed by an airstrike Friday but Ghoga's comments provided the first confirmation.
NATO spokeswoman Oana Lungescu said the alliance was investigating the reports, and appeared to suggest that its aircraft on patrol had encountered ground fire and retaliated.
"The exact details are hard to verify because we have no reliable source on the ground," Lungescu said. "Clearly, if someone fires at one of our aircraft they have the right to defend themselves."
Mohammad Bedrise, a doctor in a nearby hospital, said three burned bodies had been brought in by men who said they had been hit after firing a heavy machine gun in the air in celebration. Idris Kadiki, a 38-year-old mechanical engineer, said he had seen an ambulance and three cars burning after an airstrike.
Rebels told The Associated Press that the fighters were hit about 12 miles (20 kilometers) east of Brega, which has gone back and forth between rebel and government hands in recent weeks.
NATO, which on Thursday took over what had been a U.S.-led military campaign to stop Gadhafi from attacking his own people, also is investigating whether other airstrikes have killed civilians in western Libya, as the Libyan government claims. The United States, meanwhile, was ending its role in combat missions Saturday, leaving that work for other nations.
Rebels control much of eastern Libya, but in the west the only significant city they hold is Misrata, which has been besieged for weeks by Gadhafi forces who have cut off water, power and food supplies.
Medical officials said Saturday that government forces killed 37 civilians over the past two days in an unrelenting campaign of shelling and sniper fire and an attack that burned down the city's main stocks of flour and sugar.
Over the past month and a half, 243 people have been killed and some 1,000 wounded, according to the medical officials, who spoke to The Associated Press on condition of anonymity for fear of retaliation.
The hospital official in Misrata said Gadhafi forces were trying to pummel the port, hoping to cut off the city's last line to the outside world. He said tanks positioned on the city's east fired shells toward the area. Other Gadhafi troops disguised in civilian cars sped to the area, firing mortars and then fleeing, he said.
Gadhafi's forces have shelled the city's outskirts and residents are piling into the heart of Misrata, crowding into the homes of relations and even unfinished buildings, the hospital official said. The reports could not be independently confirmed.
Ukraine said it would dispatch a military ship to Tripoli, the Libyan capital, to collect up to 600 Ukrainians, Americans, Britons, Russians, Belorussians and other foreigners, Ukrainian spokesman Aleksandr Dikusarov said. He said Libyan authorities had guaranteed the safety of the evacuation.
Gadhafi's government is trying to hold talks with the U.S., Britain and France in hopes of ending the air campaign, said Abdul-Ati al-Obeidi, a former Libyan prime minister who has served as a Gadhafi envoy during the crisis. "We are trying to find a mutual solution," he told Britain's Channel 4 News on Friday.
At the same time, Libyan officials scoffed at the rebels' offer of a cease-fire. The rebels set one condition: that Gadhafi pulls his military forces out of cities and allows peaceful protests against his regime.
"You are not making peace if you are making impossible demands," government spokesman Moussa Ibrahim said. "It's a trick, it's a trick. I could say to the rebels, I offer you peace - get out of Benghazi on a ship. This is my condition. You can't do that."
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