Afghans commemorated the fifth anniversary of the assassination of an iconic anti-Taliban commander Saturday under the shadow of the deadliest bombing in Kabul since the overthrow of the hardline Islamic regime.

Afghan soldiers searched cars and set up checkpoints on roads leading into the city, a day after a car bomber rammed into a U.S. military convoy near the American Embassy, killing 16 people. Two U.S. soldiers were among 29 other people wounded in the attack, the most brazen yet on Kabul's heavily guarded center.

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It was some of the worst violence in Afghanistan since the U.S.-led invasion that toppled the Taliban. On Saturday, NATO and Afghan forces killed more than 30 suspected Taliban militants and destroyed several insurgent compounds during a major offensive in southern Afghanistan, NATO said.

Attacks have been increasing in Kabul but remain rare compared to the country's south. Friday's blast revealed the lingering vulnerability of foreign troops, local forces and Afghan civilians to terrorist attacks almost five years after a pro-American government was installed.

Thousands of people attended a memorial ceremony for mujahedeen leader Ahmad Shah Massood, who was killed in Al Qaeda bombing in northern Afghanistan two days before the Sept. 11, 2001 terror attacks in the United States.

"Massood was a great martyr for this land and like him, today, each son of this country is ready to sacrifice his life to make the nation free," President Hamid Karzai told the crowd at the national stadium. "We are still not free and our nation's children are still being sacrificed like yesterday in Kabul when more people were martyred in a terrorist attack."

Massood was the most famous mujadeen commander against the Soviet occupation of Afghanistan during the 1980s, and later led the resistance to the Taliban after the hardline militia seized power in 1996.

When the Northern Alliance, backed by U.S. air power, toppled the Taliban in late 2001, Massood became the most powerful symbol of the new Afghanistan. His portrait adorns public spaces and government offices.

Although widely admired for his resistance of the Soviets, he's also a divisive figure in this ethnically diverse nation. Fellow ethnic Tajiks see him as a hero, but Pashtuns, who supplied the main backing to the Taliban, compare him to other warlords who fought a brutal civil war after the Soviet pullout.

Ali Shah Paktiawal, criminal director of the Kabul police, said he did not think Friday's bombing was timed to coincide with the Massood commemoration, saying terrorists used any opportunity to attack foreign forces. He said police were investigating, but have made no arrests.

The U.S. military blamed "Taliban extremists" for the blast, which occurred 50 yards from the landmark Massood Square that leads to the main gate of the heavily fortified American Embassy compound.

A purported Taliban spokesman claimed responsibility for the bombing, according to the privately run Pajhwok Afghan News Agency. Qari Yousaf Ahmadi, whose exact ties to the Taliban leadership are unclear, claimed only U.S. and Afghan soldiers were killed in the attack, the agency said.

The blast shattered every window in a five-story apartment block facing the bomb scene, spraying shards of glass over children eating their breakfasts and women cleaning their cramped homes. A woman in her 70s and her granddaughter were among those killed.

Taliban holdouts have turned to Iraqi-style tactics in their fight to derail Karzai's U.S.-backed government, including an increasing number of suicide bombings.

Some 20,000 NATO soldiers and a similar number of U.S. forces are trying to crush the emboldened Taliban insurgency. The heaviest fighting takes place across vast desert plains in southern Helmand and Kandahar provinces, also the center of the country's huge opium trade.

NATO and Afghan forces using airstrikes, artillery and mortars killed more than 30 suspected Taliban militants in Kandahar's Panjwayi district Saturday, said Maj. Scott Lundy, a NATO spokesman. No NATO and Afghan forces were hurt. At least 320 militants have been killed since the anti-Taliban Operation Medusa offensive began Sept. 2, according to NATO.

A top Taliban commander and a spokesman for the militia have strongly disputed NATO's claims. Reporters cannot access the scene of battle to verify the death toll.

CountryWatch: Afghanistan