A roadside bomb in eastern Afghanistan killed four NATO troops Sunday, as bombings and clashes elsewhere in the country killed 14 other people, officials said.
NATO did not disclose the victims' nationalities or the exact location of the blast. Most of the troops in the country's east are American, though other countries also participate in operations there.
The Taliban regularly use roadside bombs against Afghan and foreign troops. Last year the number of such attacks rose by 30 percent, according to NATO figures.
Thousands of new American troops are joining the fight in Afghanistan this year, trying to reverse Taliban gains and help extend the governance in remote parts of the country.
The center of the Taliban insurgency is in southern Afghanistan, where a roadside bomb hit a convoy carrying the mayor of Kandahar city on Sunday, killing a civilian and wounding two others, said Najibullah Khan, a police spokesman. The mayor survived the blast.
Separately, a suicide bomber on foot in the capital of Kabul killed two Afghan civilians, said Lt. Gen. Abdul Rahman Rahman, Kabul's police chief.
The bomber — who had been targeting a NATO patrol — also wounded 14 other civilians, the Interior Ministry said in a statement. No foreign troops were wounded or killed, the statement said.
In Kandahar's Maywand district, the U.S. coalition and Afghan special forces conducting a raid in Kandahar's Maywand district — aimed at a network supporting foreign fighters in the area — killed five militants "who maneuvered on the force ... during the operation," a U.S. military statement said.
The Taliban-led insurgency has recently made a comeback the last three years after what appeared to be an initial defeat following the U.S. invasion in 2001.
Thousands of new U.S. troops are joining British, Canadian and Dutch forces in the region to battle insurgents and extend governance.
On Saturday, meanwhile, a French soldier and five Afghan troops were killed during a clash with militants in Kapisa province, officials said Sunday.
Cmdr. Christophe Prazuck, spokesman for France's Defense Ministry, said the operation involved air support from Predator drones and other allied aircraft, and that dozens of militants "were hit hard." He didn't provide casualty estimates.
France has 3,300 troops fighting in NATO- and U.S.-led military operations in Afghanistan.
Rahmatullah Safi, Kapisa's deputy governor, said five Afghan soldiers were also killed in the operation.