KABUL, Afghanistan -- Forces of a northern strongman overran the capital of a remote Afghan province Thursday, the interior minister said, in a burst of factional violence undermining the authority of U.S.-backed President Hamid Karzai.

In the south, clashes left at least seven people dead, including two Afghan soldiers, and two police officers killed in an attack by suspected Taliban, officials said Thursday. A militant also was killed and an American soldier was wounded.

Troops loyal to ethnic Uzbek warlord Abdul Rashid Dostum swept into Maymana, the center of Faryab province, 260 miles northwest of Kabul, on Thursday morning, Interior Minister Ali Ahmad Jalali said.

"Today, at 10 o'clock, militia troops loyal to General Dostum entered Maymana city," Jalali said. "They have control of the city."

Jalali said there were no reports of casualties, but Dostum aides said guards had fired on a crowd, killing four, as Gov. Enayatullah Enayat was rushed to an airport.

Fighters swarming in front of the offices of the Kabul-appointed governor fired into the air and threw rocks at the building, the minister said.

"What General Dostum has done is against all military rules and the constitution of Afghanistan," Jalali told a news conference.

The fighting was bad news for Karzai, and sure to lead to deep concern in Washington over the future stability of Afghanistan, just as American forces are facing a surge of violence in Iraq.

The city of Maymana fell before the arrival of hundreds of U.S.-trained Afghan soldiers, who left Kabul for Faryab on Thursday afternoon. It was the second major burst of militia violence to rock Afghanistan in less than a month, and threw into further doubt this country's readiness for national elections scheduled for September.

Trucks and pickups had ferried hundreds of green-bereted Afghan National Army troops armed with assault rifles and machine-guns to Kabul airport.

Some clambered into a transporter provided by the U.S.-led military coalition, which flew them toward Faryab, while others waited for a second aircraft.

Officials in Faryab have accused Dostum, who has maintained a large private army and strong political control in the region since the fall of the Taliban in late 2001, of trying to drive them out of office for allying too closely with Karzai's central government.

A Dostum aide in Kabul said the Uzbek strongman had discussed the situation in Faryab with elders from that province, but ordered no moves against Enayat or Hashim Khan, the commander of the 200th Afghan army division, who Jalali said had also fled Maymana.

The aide, Akbar Boy, said government troops were welcome in the region, but suggested there would be a violent backlash if they sided with the embattled officials, whom he accused of using government funds to try to buy votes and influence ahead of September's elections.

The clash comes less than a month after the government sent 1,500 soldiers to the western city of Herat after bloody battles between rival factions left 16 people dead, including a Cabinet minister.

Among the deaths in southern Afghanistan, a militant and an Afghan soldier were killed in a gunbattle that also left an American soldier and a second Afghan wounded, the U.S. military said.

The soldiers were not identified and no details of their injuries were given. Shooting broke out Wednesday during a joint Afghan-U.S. operation near Gereshk, 220 miles southwest of the capital Kabul, in Helmand province, U.S. military spokeswoman Michele DeWerth said.

Separately, two suspected Taliban were reported killed in a gunbattle in Sangin district when they attacked an Afghan militia checkpoint, security officials said.

The spreading violence has compounded concern that September's elections will be spoiled by militant attacks and voter intimidation.

The government has vowed to disarm some 40,000 militia fighters and round up heavy weapons around the country in time for the vote.