Taliban fighters pose with weapons as they sit in their compound at an undisclosed location in southern Afghanistan
Taliban fighters pose with weapons as they sit in their compound at an undisclosed location in southern Afghanistan in this May 5, 2011. Reuters

A large Taliban truck bomb detonated outside an American military based in Afghanistan has left at least two Afghan civilians dead and leaving as many as 77 NATO personnel injured, officials said Sunday.

The injured NATO troops were mostly Americans, a U.S. defense official said of the bombing, for which the Taliban has claimed responsibility. NATO's International Security Assistance Force has also confirmed the attack was carried out by a Taliban suicide bomber.

The massive truck bomb was detonated Saturday night in the Sayedabad district of Wardak province in Afghanistan. Last month, insurgents shot down a U.S. Chinook helicopter in the same area, killing 30 American troops, including 22 from the elite Navy SEALs unit that killed Osama bin Laden in May.

No Americans died in Saturday's bombing, yet the strike is one of the biggest insurgent attacks on a Western military installation in Afghanistan. The attack occurred on the evening before the 10th anniversary of al-Qaida's attack on the United States, which killed almost 3,000 on Sept. 11, 2001.

This attack was a high-profile attack. It was a pretty significant suicide vehicle bomb, Gen. John R. Allen, commander of coalition and U.S. forces in Afghanistan, told CNN's Suzanne Malveaux Sunday.

Allen told CNN the attack indicates, however, more about what the Taliban can't do than what the organization is capable of doing.

They have been ejected from the population in so many places around the country that their only ability to influence the battlefield on many occasions is simply to go for a high-profile attack. And that's how we view this particular attack, he said.

NATO confirmed Sunday that 77 of its personnel were injured and that two Afghan civilians had died from the attack. NATO's ISAF said the bomber was driving a truck carrying firewood, and that the driver detonated his explosives at an entry point to the base. Although the attack happened Saturday, NATO's ISAF did not disclose it until Sunday.

Military officials have said most of the 77 troops injured in the bomb did not sustain life-threatening wounds.

Most of the force of the explosion was absorbed by the protective barrier at the outpost entrance and though there were a significant number of injuries ... none is immediately life threatening, the ISAF said in a statement.

The September attack follows grim U.S. military results in Afghanistan from August -- the deadliest month for U.S. forces in Afghanistan since the nation's war in that country began. Seventy-one U.S. troops died in August, more than the 65 that died in July, 2010.

NATO is currently in the process of drawing down troops in Afghanistan, while attempting to hand over security control in the country to national forces. The U.S. has 10,000 troops scheduled to depart Afghanistan by year's end, with all U.S. military scheduled to be out of the country by the end of 2014.

The Taliban said in a statement after the bombing, when claiming responsibility, that a martyrdom-seeking attacker blew up a track loaded with explosives outside the U.S. military base. The group claimed that as many as 50 U.S. troops were killed, but NATO officials said that claim was erroneous -- that no military lives were taken in the bombing.