Three American soldiers were killed and two were wounded Wednesday in a roadside bombing in troubled northwestern Pakistan that killed 10 people, including a Pakistani soldier and three children.
The deaths were the first known U.S. military casualties in Pakistan since 1979, when a Marine guard was killed as a mob stormed the American Embassy in Islamabad.
The Pakistani Taliban claimed responsibility for the attack, which came as a five-vehicle military convoy passed a girls school in the Dir district, part of the Swat region that a Pakistani military offensive last year supposedly had cleared of Taliban.
The bombing, which followed the reported death of a top Taliban leader after a U.S. missile strike, revealed both the Pakistani insurgents' resilience and the low-profile and sometimes covert American military presence along Pakistan's remote border with Afghanistan.
Although the U.S. and Pakistani military and intelligence services are cooperating in the battle against Islamic extremists, including targeting extremists for attacks by U.S. drone aircraft, the efforts have been kept quiet in an attempt to avoid inciting more anti-American sentiment in Pakistan.
Islamic extremists promised more such assaults, which could threaten the long U.S. supply line from the Pakistani port of Karachi through western Pakistan to American and allied troops in Afghanistan.
More than 100 children were injured in Wednesday's blast, which reduced the school to rubble and trapped girls beneath the debris, screaming for help.
One young girl, whose name was given only as Samina, told Pakistani news media: "Our teacher was teaching us Islamic education when the explosion caused the roof of our class to cave in."
The attack is likely to be a propaganda victory for the Pakistani Taliban. For years, the militant Islamists have been criticized for pursuing jihad against their own people rather than against foreign troops in neighboring Afghanistan.
"This gives justification to the (Pakistani) Taliban. They keep saying they want to fight against America. And here they are, the Americans, in Pakistan," said Mehmood Shah, an analyst who formerly was a senior Pakistani security official.
According to the U.S. Embassy in Islamabad, the American soldiers were training Pakistan's paramilitary Frontier Corps, which is based in the northwest, on the front line in the battle against the Taliban and other extremists.
Lt. Col. Mark Wright, a Pentagon spokesman, said that "a few dozen" U.S. soldiers were involved in the counterinsurgency training program "at the invitation of the Pakistani government."
A military official in Washington, speaking on the condition of anonymity because he isn't authorized to discuss the operation, said the soldiers were part of a Special Operations Forces team that had been training the Frontier Corps for 18 months.
It appeared most likely that the bomb was remote-controlled, suggesting that the extremists had intelligence on the route and timing of the convoy. However, Richard Holbrooke, the U.S. special envoy for Pakistan and Afghanistan, said in Washington that there was "nothing secret" about the American training mission and that the attackers got lucky.
The U.S. soldiers were on their way to the inauguration of another girls' school in Dir that was rebuilt with American aid money after the Taliban destroyed it. The militants destroyed scores of girls' schools in the Swat region when they took it over from 2007 to April 2009, when Pakistani forces launched a counteroffensive.
The Taliban have shown repeatedly that they retain the ability to mount terrorist attacks despite a Pakistani assault on their bases in Swat and, more recently, in South Waziristan on the Afghan border.
Washington is pressing Pakistan to expand its military operation to include areas of the country that Afghan insurgents use as sanctuaries. The top U.S. military commander for the region, Army Gen. David Petraeus, who reportedly is on his way to Pakistan, said Wednesday that he understood the constraints.
"Given the way the (Pakistani) military is stretched, it's understandable that poking more short sticks into hornets' nests becomes a difficult proposition," Petraeus said.
(Shah is a McClatchy special correspondent.)
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