American military helicopters are for the first time involved in an operation against Osama bin Laden-led militants from the terrorist organisation Al-Qaeda in the Tora Bora area in the south of Nangarhar province, bordering on Pakistan. On Thursday, US helicopters were flying above the Spinghar mountain range ferreting out foreign mercenaries, who are trying to escape to Pakistan. The Qatar-based Al-Jazeera television station reports that American B-52 bombers dealt five or six strikes on the Al-Qaeda positions atop a mountain. A napalm bomb was used, reports an Al Jazeera correspondent. Earlier, Al-Jazeera reported that an AC-130 fire-support plane was used and a vacuum bomb was dropped. According to Al-Jazeera, there are now 60 British and 40 American rangers found in the Tora Bora region. On Thursday, the Pashtoon command of the tribal emergency volunteer corps in the Melawa and Tora Bora areas announced the start of an offensive on the Al-Qaeda positions.