MASHAKHAIL, Afghanistan -- The strangers came in the middle of the night. They tied up the school caretakers with turbans and shoved them into a classroom. Then they broke the school windows, poured fuel everywhere and set the principal's office on fire.

The results were much the same as in other schools recently burned in Afghanistan: damage and fear. The men, who hid their faces behind scarves, burned 16 carpets, 15 chairs, five desks, four caretakers' beds, three bookshelves, all school records back to 1988 and 1,300 books, including a Koran. The white concrete walls of two rooms and the ceilings were stained black by smoke after last month's attack.

"God may drown them in the water," said Nasrullah, the boys' headmaster, who uses one name like many Afghans. "Because they were not Muslim. If they were, they never would have burned the Holy Koran."

In the last six months, education has been under attack in southern and southeastern Afghanistan in an apparent attempt to erode what hope people still have in the weak central government and to panic them about their children's safety. Up to 50 schools have been set on fire, according to the country's Education Ministry. Up to 300 have shut down at some point, largely out of fear. Many parents are nervous about sending their children to school.

"The education system in some southern provinces has not completely collapsed, but it is push and pull," said Mohammad Sediq Patman, the deputy education minister. "One month, the enemy warns people not to go to school, and kids stay at home. The next month, school is back to normal. It is a way of fighting for the enemy."

No one has been arrested in any of the attacks, Education Ministry officials said. The attackers just fade away. Some blame the Taliban or other insurgents or tribal rivalries.

Reputed Taliban spokesman Mohammed Hanif said the Taliban burned only schools that preached against Islam and Islamic fighters.

"We have not threatened anybody except those who work for Christians and for foreigners in Afghanistan," Hanif said in a telephone interview. "We have never killed any teacher or any student."

All told, the United Nations has counted at least 30 serious attacks on schools and teachers in recent months. Thirteen people have been killed: five staff members and eight students.

On Tuesday, a rocket exploded in a crowded school courtyard in eastern Kunar province, killing seven children. Government officials blamed the Taliban.

A high school teacher was beheaded in southern Zabul province in January. In December, a teacher was dragged out of his classroom in southern Helmand province and shot.

In 200 communities there has been some form of intimidation, often letters hung on doors at night that warn parents not to send their children to school or warn teachers not to work.

"It's not easy to point out what the motivation is," said Edward Carwardine, a spokesman for UNICEF, the United Nations' children's agency. "But it may be that education is seen as a very visible sign of progress."

Since the fall of the Taliban in late 2001, education has been a major focus of rebuilding in the war-torn country; enrollment in primary and secondary schools has jumped from 900,000 to more than 5 million. The Taliban did not allow girls to go to school. Boys were sent to Islamic schools to study only religion.

There had been sporadic attacks on schools after the Taliban fled, but mainly on girls' schools. What has happened in the last six months is different. And it's spreading from more dangerous provinces such as Helmand and Kandahar eastward to relatively calm Laghman province and Mashakhail.

Patman, the deputy education minister, said officials have started broadcasting radio ads in which he warns those responsible that they are not just burning schools, they are burning their children's future.

"This is the fault of fighting and war in this country," Patman said. "The problem we have is the level of education is very low. That's why people are misused."

The Mashakhail school, attacked at 1 a.m., was the fourth to be torched in Laghman province in two months. The principal suspects the school was targeted because it enrolls girls.

Police are split on who was responsible. The colonel in charge of the crime department blamed Al Qaeda. The deputy commander blamed tribal rivalries.

Unlike in many other communities, the villagers here decided to fight back. They put out the fire with blankets full of soil. They also started protecting the school on their own; the five nearest villages each send an armed man every night. Parents sent their children to school the next day despite their fear.

On a recent day, classes were crowded with students from the eight surrounding villages. School officials said they had not seen attendance dip since the attack, with 530 girls and 700 boys showing up for class.

"My mom told me, `Go ahead, go to school,'" said Mohammad Yusuf, 8 and a 1st grader. "I ran here. This is the place we study. As soon as I found out it was set on fire, I was so sad."