The NATO chief spoke hours after the operation's deputy commander, British Rear Adm. Russell Harding, refused to apologize. Harding said the alliance was unaware the fighters were using tanks in their campaign against Muammar Qaddafi's forces, and said it was becoming hard to distinguish between the two sides on the road between Brega and Ajdabiyah.
On Friday, opposition fighters were seen hastily painting the roofs of their vehicles bright pink to avoid more friendly fire casualties.
A UN panel said Friday several hundred foreign fighters are likely operating in Libya and may be involved in serious human rights violations. The head of the UN working group on the use of mercenaries said there is evidence foreign fighters are being used by both sides.
Jose Luis Gomez del Prado said the panel has multiple sources confirming Qaddafi "has used mercenaries and is using mercenaries." He said the fighters are believed to come from Africa and Belarus.
Del Prado said private security firms are supplying some of Qaddafi's fighters and the opposition may also have foreign fighters in their ranks.
Meanwhile, Scottish prosecutors said Friday they have interviewed Libya's ex-Foreign Minister Moussa Koussa as part of an investigation into the 1988 bombing of a passenger jet over Lockerbie, Scotland.
Scottish lawmaker Alex Salmond said Koussa may be able to provide more information about who authorized the bombing, which killed all 259 people aboard the Pan Am jet and 11 people on the ground.
British government officials said Koussa was being treated as a witness, rather than a suspect in the case.
