ASADABAD, Afghanistan, (Reuters) – A rocket hit an open-air Afghan school in the yard of a mosque on Tuesday, killing six children and wounding about 30.

Taliban or allied militants were believed responsible for the latest attack in an intensified insurgency that has brought a wave of suicide and roadside bombs, raids and ambushes in different parts of the country.

“Two rockets were fired … one hit the compound of a primary school where children including girls were busy studying,” said deputy provincial police chief Mohammad Hassan Farahi.

The government condemned the killing of the six children as a despicable attack on the country’s youth and blamed “enemies of Afghanistan”, a reference to the Taliban and their allies.

About 180 children were at the school in the courtyard of a mosque outside Asadabad, capital of the eastern province of Kunar, when the rocket hit.

Text books and pieces of flesh littered the ground as distraught parents arrived hunting for their children, a Reuters reporter said.

Wounded children and teachers were taken to a hospital run by the U.S. military and one in Asadabad.

The reporter counted about 30 wounded people, most of them children, at the hospitals. Ten people were discharged after treatment, the others were more seriously hurt.

Taliban militants have attacked and burned schools as part of their campaign against the government but it was not clear if the school hit on Monday was a target.

A second rocket hit a police base some distance away. The provincial governor said no one was hurt in that blast.

Kunar, on the Pakistani border, is one of Afghanistan’s most violent provinces. At least 20 American soldiers have been killed there since June.

Shortly after the attack, a bomb went off in a ditch beside a road in the centre of the eastern city of Jalalabad, 80 km (50 miles) southwest of Asadabad, wounding five passers-by, said a doctor at a city hospital.

The bomb was near offices of several foreign aid groups but police said the target was not clear.

The Taliban, fighting since their overthrow in late 2001 to force foreign troops out and topple the Western-backed government, have claimed responsibility for many of the attacks across the country in recent weeks.

There were no immediate claims for the rocket attack or the Jalalabad blast.

The violence has followed a Taliban announcement late last month they had launched a spring offensive and comes as NATO members are preparing to send in thousands more peacekeepers.

The U.S. military says the insurgents are unable to mount large-scale guerrilla attacks, after suffering heavy losses this time last year, and are resorting to bombs to break the will of the people and put off the government’s foreign backers.

Britain, Canada and the Netherlands are leading a NATO expansion into the south as the United States hopes to cut its Afghan force by several thousand to about 16,500.

NATO is due to take over responsibility for the east, including Kunar, this year.

Four U.S. soldiers were killed in a roadside blast in the mountainous province last month and 16 U.S. troops were killed last June when insurgents shot down their helicopter with a rocket-propelled grenade.

Five U.S. troops were wounded in a blast in Kunar on April 1.