NATO-led forces and Afghan troops clashed with suspected Taliban militants in southern Afghanistan Thursday, leaving as many as 20 suspected insurgents dead, while a suicide bomber struck a vehicle carrying Afghan soldiers in the east, wounding 16 people, officials said.

Some 60 insurgents attacked a joint NATO and Afghan patrol in the southern Kandahar province's Panjwayi district, said Squadron Leader Jason Chalk, a spokesman for the NATO-led troops.

The troops returned fire and called in airstrikes on insurgent positions that left up to 20 insurgents killed and two suspected Taliban detained, Chalk said. There were no casualties among NATO or Afghan troops, he said.

It was impossible to independently verify the death toll at the remote battle site.

The clash came a day after NATO said that clashes with insurgents in the area have decreased.

CountryWatch: Afghanistan

In the east of the country, the suicide bomber on foot rushed to the vehicle carrying Afghan troops in Khost province and sparked a blast that killed himself, wounded two of the troops and 14 civilians, said Mohammad Ayub, a provincial police chief.

Separately, a car bomb targeting a U.S. patrol in Tani district of Khost province wounded three civilians on Thursday, Ayub said. No U.S. troops were injured in the blast, he said.

In the southern city of Kandahar, two people riding a motorbike lobbed two hand-grenades at the Indian Consulate building on Thursday, said Abdul Shakoor Khan, a police official. No one was injured, he said.

Afghanistan is going through its worst period of violence since 2001, particularly in the south and east of the country, where insurgents have been battling Afghan and foreign troops.

While NATO said the clashes with insurgents have decreased in the last month, the militants are increasingly resorting to the use of roadside and suicide attacks in their campaign to weaken the government.

On Wednesday, suspected Taliban militants ambushed a joint Afghan-NATO patrol in southern Uruzgan province, killing one Afghan soldier and wounding three others, said Gen. Mohammad Qasam Khan, the province's police chief.

A roadside bomb exploded near a vehicle carrying Afghan soldiers, then militants opened fire on the patrol. One militant was killed in the ensuing clash, Khan said.

But a NATO statement on Thursday said that 25 suspected insurgents and one local were killed in the battle. Seven local civilians were also wounded, the statement said. No NATO troops were wounded in the clash.

It was no immediately clear the difference in the reported number of causalities.

Meanwhile, a U.S. soldier died after falling from a helicopter during a landing approach in southern Afghanistan, NATO said Thursday.

The soldier, who name was not released, was taken to a military hospital after falling from the UH-60 helicopter in Helmand province Wednesday, the alliance said. He died of his injuries in the Kandahar military hospital.

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