MAIDUGURI, Nigeria — Heavily armed Islamic extremists abducted at least 100 female students from a school in northeast Nigeria before dawn Tuesday, but some of the teens managed to escape from the back of an open truck, officials said.

The tragedy came one day after a bombing killed more than 70 people in the city of Abuja.

The girls were seized after midnight from a school in Chibok, on the edge of the Sambisa Forest, an insurgent hideout, said Borno state police commissioner Tanko Lawan.

Gunmen killed a soldier and police officer guarding the school, then took off with at least 100 students, a State Security Service official said.

Witnesses said the gunmen arrived in trucks and motorcycles and may have grabbed as many as 200 girls.

Audu Musa, who teaches in another school in the area, said he saw eight bodies in the area.

“Things are very bad here and everybody is sad,” he said, according to Britain’s Telegraph newspaper.

The local government official said he did not know how many of the girls escaped but that “many” have walked through the bushes and back to Chibok.

The girls were piled into the back of an open truck and, as it was traveling, some grabbed at low-hanging branches to swing off while others jumped off a slow-moving vehicle, he said.

One girl told the BBC that the truck convoy had to slow down when one of the trucks developed a fault, providing the opportunity to escape.

The girl said she and her fellow students were sleeping when armed men burst into their hostel and told them not to panic.

“We found out later that they were among the attackers,” she said.

All schools in Borno state were closed three weeks ago because of an increasing number of attacks by militants who have killed hundreds of students in the past year.

But the young women — between 16 and 18 years old — were recalled to take their final exams, the local government official explained.

Islamic extremists have been abducting girls to use as cooks and sex slaves.

Insurgents from the Boko Haram terrorist network are blamed for attacks that have killed more than 1,500 people this year.

The group — whose name means “Western education is forbidden” — has targeted schools, mosques, churches, villages and agricultural centers in increasingly indiscriminate attacks. It has also made daring raids on military barracks and bases.

Boko Haram is also accused of Monday morning’s explosion at a busy bus station in Nigeria’s capital that killed at least 75 people and wounded 141.