KABUL: German soldiers traveling to the scene of a deadly firefight with Taliban insurgents accidentally killed six Afghan troops, the Afghan military said Saturday. Three Germans died in the firefight with the militants.

The friendly fire incident Friday took place in northern Kunduz province, where German forces were sharply criticized last September when they ordered an airstrike on two tanker trucks that had been captured by the Taliban. Up to 142 people died, many of them civilians.

The German central command confirmed Friday's incident, but put the number of Afghan troop casualties at five. The deaths occurred amid heavy fighting between German troops and militants near Kunduz city.

Meanwhile in Kabul, the speaker of the lower house of parliament criticized President Hamid Karzai for blaming the international community Thursday for the vote fraud controversy over last year's disputed presidential election.

Yunus Qanooni also blasted Karzai's claim of foreign interference in the drafting of the nation's electoral law, which the president had sought to amend this week to expand his control over the country's institutions.

"This is the house of the people and all the members have been elected," Qanooni said. "It's not possible that we would be influenced by foreigners."

Karzai called U.S. Secretary of State Hillary Rodham Clinton Friday after the Obama administration expressed dismay at his remarks — a sign of the increasingly uneasy relations between the Afghan leader and key international allies whose forces support his weak government against a powerful Taliban insurgency.

Militants have long been active in the volatile south and east, but once stable northern areas have also come under growing militant influence, including Kunduz. The Taliban presence there threatens a key NATO military supply line that opened last year following painstaking negotiations between neighboring counties and the United States.

The land route via Russia and Central Asia offers an alternative means of trucking in essential supplies to the 120,000-strong NATO force in Afghanistan. Most supplies come in overland from Pakistan along a corridor that has been frequently attacked by militants.

Commenting on Friday's friendly fire incident, the German military said its soldiers were rushing from Kunduz to the scene of fighting with militants shortly after 7:00 p.m. when they encountered two civilian vehicles and demanded that they stop. When they did not, a German armored personnel carrier opened fire on them, its statement said. The vehicles were later found to have been transporting Afghan troops and an investigation is pending, the military added.

Shortly before, German troops had been attacked while on a bridge-building and mine-clearing mission southwest of Kunduz city.

Kunduz provincial government spokesman Muhboballuh Sayedi said Afghan commanders were meeting on Saturday with coalition forces to discuss the incident. The Afghan Defense Ministry condemned the deaths of its soldiers.

The German commander in northern Afghanistan, Brig. Gen. Frank Leidenberger, called his Afghan counterpart soon after the friendly fire incident to "express his profound dismay," the German military said.

Spokesman for the German Central Command Joerg Langer said troops had warned the oncoming vehicles but were unable to see who was inside because of failing light.

"We obviously regret this incident very much," Langer told The Associated Press in Berlin. He declined to give further details citing the ongoing investigation.

The German military said Friday's battle with militants continued until about 11:30 p.m. and German troops were still patrolling the area. The bodies of the three soldiers were to be repatriated to Germany on Saturday, it said.

Kunduz is one of the principal bases for the 4,300 German troops currently deployed in Afghanistan. The German parliament recently approved the deployment of 850 reinforcements.

Elsewhere in Kunduz on Friday, an apparent rocket attack on an Afghan military base killed a small child and injured two women, the Interior Ministry reported. Another three civilians were killed in a pair of roadside bomb attacks in the eastern province of Khost, the ministry said.

NATO announced that a coalition soldier was killed by an improvised explosive device in southern Afghanistan on Friday.

In the latest assassination of a government figure, gunmen opened fire and killed a deputy district police chief on his way to work in Baglan province bordering Kunduz, the Interior Ministry said.