A suicide attack and a roadside bomb killed 15 Afghan security guards, part of a spate of violence that left 35 people around Afghanistan dead, including a British soldier, officials said Wednesday.
Taliban militants are behind a relentless wave of attacks in Afghanistan, eight years after the U.S.-led invasion.
President Barack Obama's administration has ordered 21,000 new U.S. troops to join the fight in a hope of reversing the Taliban gains.
At the main U.S. base in Bagram on Wednesday, Maj. Gen. Curtis Scaparrotti, commander of the 82nd Airborne Division, took over command of all troops in eastern Afghanistan from outgoing Maj. Gen. Jeffrey Schloesser, commander of the 101st Airborne Division.
The commander of U.S. and NATO troops in Afghanistan, Gen. David McKiernan, told several hundred troops and Afghan leaders at the ceremony that historians will point to the 101st's 15 months in Afghanistan "as a key shift in momentum" in the war.
McKiernan, who has served as commander for one year, is soon to be replaced by Lt. Gen. Stanley McChrystal after having his two-year deployment cut short by Defense Secretary Robert Gates.
The suicide bomber on a motorbike attacked a convoy of Afghan security guards ferrying supplies to international troops on Wednesday, killing five of them. The attack in Spin Boldak district of Khandahar occurred about a mile from the Pakistan border, said district police chief Safiullah Khan.
A day earlier, another convoy in eastern Paktika province was initially hit by a blast that killed one security guard, said police chief Azizullah Wardak. A second improvised explosive device then ripped through the convoy and killed nine guards in another vehicle, Wardak said.
The Afghan guards were based with U.S. troops in the area. It was unclear what security company they were working for or if they were traveling with American forces.
The attack came as 11 Taliban militants were killed in a joint operation by coalition and Afghan troops in southern Afghanistan. Coalition and Afghan troops attacked the militants in a compound Tuesday night in southern Zabul province, said police chief Abdul Rahman Sarjang.
Also Tuesday, two policemen were killed and five others were wounded in a roadside bomb blast in southern Kandahar province. The police were on a patrol in Zhari district when their vehicle struck a roadside bomb, which also wounded five officers, said Bismaullah Khan, Zhari district police chief.
Separately, a roadside bomb killed a British soldier in the NATO-led force on Tuesday in Helmand, Britain's defense ministry said.
In another incident on Tuesday six Taliban militants were killed in a fighting with Afghan security forces in Kandahar province, said army Gen. Sher Mohammad Zazai. He also said that two police officers were wounded in the gun battle.
As newly arriving Marines enter violent Afghan south — the spiritual home of the Taliban and the country's major drug-producing region — the military said Tuesday that U.S. deaths will likely increase even further this summer.
U.S. experts say they expect improvised explosive device attacks — roadside bombs and suicide attacks — to rise 50 percent this year, contributing to the increase in casualties.
An Associated Press tally that found U.S. deaths in Afghanistan have risen to 65 so far this year, up from 36 over the first five months of 2008 — though U.S. and coalition troops have also killed hundreds more militants.
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