NATO and Afghan troops battled militants in southern Afghanistan in a clash that killed 52 suspected insurgents, a statement from the alliance said Monday.

The hours-long clash took place in the Charchino district of Uruzgan province on Sunday, the statement said. There were no reports of NATO casualties.

It was impossible to independently verify the number of militants NATO said died in the battle.

In other violence, three government officials going to investigate the burning of a school in eastern Afghanistan were killed after a roadside bomb ripped apart their vehicle and two Taliban fighters were killed in a gunbattle with police in Kandahar province.

The three officials — a district police chief, intelligence chief and administrative chief — were going to investigate the overnight burning of a school in the Khogyani district of Nangarhar province, said Gen. Abdul Basir Salangi, the provincial police chief.

On their way to the school, a remote-controlled roadside bomb exploded. Two police were also injured, Salangi said.

CountryWatch: Afghanistan

Militants have been stepping up attacks across Afghanistan in recent months, including the use of suicide and roadside bombs. More than 150 schools have been attacked this year across the country, education officials say.

In the southern province of Kandahar, armed militants kidnapped a Pakistani engineer who was working with a construction team. Police officers protecting the construction crew returned fire, killing two Taliban fighters, said Dund district chief Hamed Wali.

Three police and the Pakistani driver of the construction crew were injured, Wali said. The militants, who were driving in several vehicles, left behind two AK-47s and one four-wheel drive vehicle, he said.

Wali said he did not know the name of the construction worker or the company he was working for.

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