KABUL, Afghanistan — In what has become an annual breakdown of law and order, the capital turned into a scene of chaos on Saturday with little visible sign of government control. Young men armed with knives and Kalashnikov rifles sped around Kabul, firing into the air and terrorizing residents, who mostly stayed indoors.

Sept. 9 is supposed to be a solemn day on the Afghan calendar, the date in 2001 when Ahmad Shah Massoud, an anti-Taliban leader, was killed by Al Qaeda just before the Sept. 11 attacks in the United States.

But year after year, the occasion has turned into a show of force by unruly supporters of Mr. Massoud, largely northerners disenchanted with the government.

The occasion highlights the Afghan political leadership’s lack of influence with disenfranchised groups in the capital, even at a time when Taliban pressure is increasing in districts and cities around the country.