NATO said Friday its airstrikes had hit rebels using tanks in their fight with the government forces in eastern Libya, but said it would not apologize for the deaths.
Rear Admiral Russell Harding, the deputy commander of the NATO operation, said NATO had no previous information the rebels were operating tanks. In the past, only forces loyal to Moammar Gadhafi had used heavy armored vehicles, he said.
Harding said the situation between the eastern coastal towns of Brega and Ajdabiya remains fluid, with the opposing forces engaged in a series of advances and retreats, making it difficult for pilots to distinguish between them.
NATO jets attacked a rebel convoy between these two towns Thursday, killing at least five fighters and destroying or damaging a number of armored vehicles.
The strikes, including an attack earlier this week, provoked angry denunciations of NATO by the rebels.
Meanwhile, NATO officials have expressed frustration with the insurgents, who now view the alliance, whose mandate is limited to protecting civilians, as their proxy air force.
Harding said Friday that NATO jets had conducted 318 sorties and struck 23 targets across Libya in the past 48 hours.
"It would appear that two of our strikes yesterday may have resulted in (rebel) deaths," he told reporters in Naples where the alliance's operational center is located.
"I am not apologizing," Harding said. "The situation on the ground was and remains extremely fluid, and until yesterday we did not have information that (rebel) forces are using tanks."
Also Friday, U.N. investigators said they would next week start probing alleged human rights violations committed in Libya by both forces loyal to Gadhafi and rebels trying to topple him.
The independent three-member commission of inquiry, headed by American war crimes expert Cherif Bassiouni, declined to reveal their exact travel schedule but said that it would stop first in Egypt and also would visit Tunisia and Libya.
He said the team would gather testimony and cooperate with the International Criminal Court (ICC) in the Hague, whose prosecutor Luis Moreno-Ocampo also is looking into possible war crimes by Gadhafi, his sons and his inner circle.