Some of the schoolgirls missing after a militant attack on a boarding school in northern Nigeria have been rescued by the military, officials say.

About 100 children were believed to be missing after pupils and teachers fled into bush outside the town of Dapchi during the attack.

Parents told the BBC they had seen girls being taken away in trucks.

The attack comes four years after Boko Haram kidnapped more than 270 girls from a school in the town of Chibok.

In a statement, the Yobe state government said an unspecified number of girls had been rescued from the “terrorists who abducted them” and were now with the army.

Reuters news agency quoted parents and a government official as saying that 76 girls had been rescued and at least 13 were still missing

Two girls had been found dead, Reuters said, without specifying how they had died.

Yobe state officials had previously said there was no information to suggest any of the girls had been kidnapped.