Kandahar, Afghanistan ? President Hamid Karzai urged neighboring Pakistan to prevent militants from training on its soil as fighting Friday in southern Afghanistan killed a U.S.-led coalition soldier and at least eight suspected Taliban militants.

The violence came amid a surge in attacks by Taliban insurgents trying to reassert control over their former southern heartland. The escalation has prompted Britain to consider sending more forces. Hundreds of people, mostly militants, have died in fighting in recent weeks.

Karzai blamed foreign terrorists for the rising violence, and called on Pakistan to dismantle terrorist training grounds on its side of the border. Pakistan, a former Taliban backer but now a key U.S. ally in its war on terrorism, denies granting sanctuary to the militants.

“A factor of instability is the continuation of terrorists being able to attack Afghanistan from abroad who are equipped, financed and sent to Afghanistan,” Karzai said during a visit to Japan.

“I hope that Afghanistan, Pakistan and the region can cooperate much more effectively and strongly, and much more sincerely, to stop terrorism and eliminate its sources of training and financing.”

Afghan boys play on a destroyed bus in Kabul, Afghanistan. Security has increased in the Afghan capital after a string of bombings in the city.

In the latest bloodshed, militants attacked a coalition convoy Thursday in Helmand province’s Baghran Valley, killing a coalition soldier and wounding another, said spokesman Sgt. Chris Miller. Five militants died when coalition forces returned fire, he said.

Miller gave no details about the dead soldier’s identity or nationality, but another foreign military official, speaking on condition of anonymity due to policy, said the soldier was American.

Elsewhere in Helmand, three suspected Taliban militants died Thursday night and two more were wounded when a bomb they were trying to plant exploded on the side of a main highway in Grishk district, said provincial police chief Ghulam Nabi Malakhail.

He said Taliban fighters attacked government offices in Khana Shien district. Police returned fire and the militants retreated after the fighting, leaving bloodstains. It wasn’t clear if any were killed or wounded.

In London, Britain’s defense secretary, Des Browne, said Thursday that he was talking with military chiefs about adding British troops to the 3,000 now in Helmand, a hub of Taliban resistance and Afghanistan’s drug trade.