Heavily armed men descended on the school as the girls slept.
Bullets flew as guards fought back, but they lost.
The men, Boko Haram militants, herded more than 100 students onto buses, vans and trucks and drove off, flanked by motorcycles, authorities said.
That was Monday. By Wednesday, just eight of the 129 abducted school girls were still missing, according to the Nigerian military.
It was not immediately clear how the girls became free. Their conditions were also not clear.
“They forced us into trucks, buses and vans, some of which were carrying foodstuffs and petrol. They left with us in a convoy into the bush,” said a student among the girls who escaped and who declined to be named for security reasons. “A group of motorcyclists flanked the convoy to ensure none of us escaped.”
At one point, one of the trucks broke down and the girls on that vehicle were transferred to another one, the student said. The broken down truck was set on fire, she added.
When another vehicle broke down and the men tried to fix it, “some of us jumped out of the vehicles and ran into the bush. We later found our way back to Chibok,” she said, referring to the northeastern town where her school is located.
Read more: CNN