ZHARI, Afghanistan — Six American soldiers were killed and more than a dozen American and Afghan soldiers were wounded on Sunday morning when a van packed with explosives detonated beside a small joint outpost in southern Afghanistan.
The soldiers were at a new strong point in a small mud-walled building near the village of Sangsar, north of the Arghandab River, when the bomber drove up to one of the building’s walls and exploded his charge at about 9 a.m.
The blast was easily audible roughly 8 miles away, and sent a dusty mushroom cloud towering over the farmland.
The explosion blasted a large hole in the thick wall, causing the roof to collapse on soldiers inside. Other soldiers quickly arrived and clawed and pulled at the waist-deep rubble to free the buried troops.
The building had been occupied by American and Afghan troops for only a few days, an American official said, and was beside a narrow road. It was not immediately clear how the vehicle managed to approach as closely as it did without being challenged or stopped.
General Abdul-Hameed, a commander in the Afghan National Army, said by telephone that his soldiers had tried to stop the van but that its driver ignored them, drove toward the building and rammed the vehicle against its exterior wall.
After the van exploded, the field beside the ruined building became a busy landing zone, as four medical evacuation helicopters landed to shuttle the victims to two military hospitals in nearby Kandahar.
The Taliban swiftly claimed responsibility for the bombing. “We have killed numbers of Americans and Afghan soldiers and wrecked and ruined their security check post,” a Taliban spokesman, Qari Yousuf Ahmadi, said by telephone. “We will carry out similar attacks in the future.”
In addition to the six killed Americans, four American soldiers were wounded, but their wounds were not life-threatening, officials familiar with their condition said. The names of the victims were withheld pending the notification of their families.
The Taliban claim of killing Afghan soldiers appeared to be unfounded.
There were conflicting official reports on the number of Afghans wounded; some reports said 11 Afghan soldiers were wounded, others put the number as high as 14. At least one Afghan soldier, who was seen by two journalists from The New York Times aboard the medevac helicopters, was gravely wounded with a head injury.
Most of the other wounded Afghans visible to the two journalists were walking under their own power, and appeared to suffer cuts and shrapnel wounds. A medical official said the remaining Afghan victims were expected to survive.
The attack occurred in an area that has had a heavy American and Afghan military presence since autumn, when NATO and Afghan forces flowed into Taliban-controlled territory of Kandahar Province in an effort to clear insurgents and bring the area under the Afghan government’s control.
The river valley, a belt of irrigated fields and small villages, is now a network of American and Afghan outposts. Patrols crisscross the region each day, and new positions — like the strong point that was attacked Sunday — are being built.
The pace of fighting has subsided in recent weeks as the weather has cooled and the leaves have fallen off the vegetation, making it more difficult for insurgents to hide.
But the Taliban has continued to plant bombs and dispatch suicide bombers, and American and Afghan soldiers are wounded or killed in the province on most days.