Reporting from Kabul, Afghanistan — A sophisticated and wide-ranging assault against the principal symbols of Western power in Afghanistan's capital on Tuesday demonstrated the insurgency's ability to strike with impunity at even the country's most heavily fortified areas.

At least six Afghans were reported killed in attacks that skittered across the city, police said, in one of the most high-profile series of strikes in Kabul in the course of the nearly decade-old war.

The daytime barrage of rockets and gunfire aimed primarily at the "green zone" — a fortress-like area containing the U.S. Embassy and the headquarters of NATO's International Security Assistance Force, or ISAF, among other facilities — came just two days after the 10th anniversary of the Sept. 11 attacks, when Western installations had been on high alert.

A U.S. Embassy spokeswoman, Kerri Hannan, said no embassy personnel were injured in the rocket barrage, which began about 1:30 p.m. and triggered a rare order that those on the embassy grounds retreat into hardened shelters. An ISAF spokesman also said no coalition personnel were hurt.

The attacks come at a time when the United States, like its NATO allies, is turning its attention to winding down the combat mission in Afghanistan. About 10,000 American troops are to depart by the end of this year, amid military officials' claims that the Taliban movement has been badly hurt by targeted strikes at its leadership tier.

The Taliban claimed responsibility for Tuesday's strikes, which paralyzed the capital for hours. The sound of sporadic gunfire continued as darkness fell, and the thudding of helicopter blades could be heard far into the night amid the echo of explosions.

"Again, again!" an elderly shopkeeper cried out in despair as he pulled down a heavy metal grate, trying to secure his carpet store. Passersby fled as the sound of gunfire and explosions rang out near one of the city's major intersections.

In the upscale neighborhood of Wazir Akbar Khan adjoining the diplomatic enclave, witnesses said one rocket fell close to a minibus carrying schoolchildren, sending them crying into the street. Several suffered minor injuries. A block over, some men shouted for help as they carried the bloodstained body of a man apparently hit by shrapnel.

The strikes closest to the embassy compound were apparently launched from the upper stories of an unfinished high-rise building about 300 yards away. In past attacks in other cities, including Kandahar, the hub of Afghanistan's south, insurgents have seized high ground — tall buildings or construction sites — close to installations they wish to target.

"I do not understand this talk of how the Americans can keep us safe," said businessman Khalid Khahir, hurrying away on foot from a busy street in the city center. "They cannot protect themselves."

Kabul city and surrounding Kabul province are nominally under the control of Afghan security forces. But the city is home to a number of large American installations, and NATO troops are generally called to respond to any large-scale incident in the capital. The June siege of the Intercontinental Hotel ended only with the intervention of North Atlantic Treaty Organization forces.

It was not immediately clear Tuesday what role, beyond providing air cover, NATO forces may have played in suppressing the latest attack.

Kabul, though relatively tranquil compared with some parts of the country, has suffered a series of high-profile assaults in recent months, including the attack on the Intercontinental and one in August on the British Council's offices.

Afghanistan's Interior Ministry reported at least nine injuries in Tuesday's attack. Officials said several suicide bombers had struck in a western area of the capital almost the same time that the diplomatic zone came under rocket attack, suggesting a tight degree of coordination rarely seen in previous assaults in Kabul.

A Taliban spokesman, Zabiullah Mujahid, said the main targets were the American Embassy, along with the Afghan intelligence service and the NATO force. He claimed that the strikes had inflicted "heavy casualties" on Westerners.

The head of criminal investigations for the Kabul police, Gen. Zaher Mohammed, said most of those killed and injured were Afghan civilians.

He said seven suicide bombers and would-be bombers were believed to have taken part in the strikes, and insisted that authorities had the situation in hand.

But residents were afraid to venture into the streets. "I don't want to drive across town tomorrow morning," said Mirwais Ahmadi, a government worker returning home to check on his family. "Who wants to risk their life?"

President Hamid Karzai condemned the attacks, insisting that they would not hamper the process of Western forces handing over security responsibility to the Afghan police and army. That process has begun in seven cities or provinces, with more to be announced this month.

"The attacks … embolden people's determination to take responsibility for their country's own affairs," the Afghan leader said in a statement.