Afghan chopper crashes kill 14 Americans

Two helicopter crashes killed 14 American troops and civilians in Afghanistan on Monday in one of the blackest days for the United States since its 2001 invasion, officials said.

As anti-US protests erupted in Kabul over the alleged burning of a Koran, Afghan President Hamid Karzai also questioned Washington's commitment to the war-torn nation ahead of a run-off election in less than a fortnight.

Following a first round riddled with fraud, Karzai's presidential rival Abdullah Abdullah called for the head of the country's election commission to be sacked.

The deadlier of the two chopper crashes was in western Badghis province where seven troops and three civilians were killed. The NATO-led force in Afghanistan said enemy fire was not believed to be the cause.

The Taliban said, however, it was behind the downing of the helicopter and claimed 14 Afghan civilians were killed in a subsequent aerial bombardment by the foreign force.

The Islamist militia also claimed to have caused a mid-air collision in the south of the country which NATO's International Security Assistance Force (ISAF) said had killed four American soldiers.

"Four ISAF service members were killed and two others injured in the incident," it said. Two helicopters apparently collided mid-air and the cause was being investigated but no hostile fire was involved, it added.

The crash in Badghis occurred during a joint search operation by Afghan and Western forces of "a suspected compound believed to harbour insurgents conducting activities related to narcotics trafficking", ISAF said.

Taliban spokesman Qari Yousuf Ahmadi told AFP the Islamists had "shot down" the helicopter in Badghis, and that 24 foreign soldiers were killed.

The single deadliest incident involving US troops in Afghanistan came in June 2005 when 16 troops on a special forces helicopter were killed when their MH-47 Chinook helicopter was shot down by insurgents.

Western Afghanistan has become increasingly hostile in recent months as the Taliban expand across the country.

ISAF said a homemade bomb killed a US soldier in eastern Afghanstain on Sunday and another died of wounds sustained in an insurgent attack.

ISAF and the defence ministry said two dozen people, including two Afghan soldiers and 22 insurgents, were killed in the south and southeast Sunday.

According to an AFP tally based on that kept by independent website icasualties.org, 437 foreign troops have died in Afghanistan in 2009, including 269 Americans.

The surge in the military death toll has increased pressure on US President Barack Obama as he considers a request by his top commander on the ground to deploy up to 40,000 more troops.

Some of his aides have said it would be irresponsible to take a decision before the scheduled run-off between Karzai and his former foreign minister Abdullah on November 7.

Karzai, who came to power in late 2001 with US backing and has been pushing for the extra troops, said that he had begun to question the commitment of his traditional allies.

"Is the United States a reliable partner with Afghanistan? Is the West a reliable partner with Afghanistan?" Karzai told CNN. "Have we received the commitments that we were given? Have we been treated like a partner?"

Anti-US sentiment is on the rise in Afghanistan, highlighted in Kabul when angry protests erupted for a second day over allegations -- denied by NATO and Afghan authorities -- that Western troops had torched a Koran earlier this month.

Witnesses and medics said Afghan police opened fire and turned a water cannon on the demonstrators, wounding at least three people.

In other unrest in the province of Nangahar, Governor Gul Agha Shairzai escaped unhurt from a grenade attack at a conference he was attending, his spokesman said. One of his assailants was gunned down, officials said.

With tensions rising ahead of the November 7 run-off ballot, Abdullah meanwhile demanded the "immediate dismissal" of Independent Election Commission chief Azizullah Ludin and his replacement by another member of the IEC.

"He has left no credibility for the institution," Abdullah told a news conference.