More than 100 Nigerian schoolgirls are missing after an attack on a boarding school by Boko Haram jihadists, Nigerian police say.

Militants raided their school on Monday evening, but many of the students and staff had fled before they arrived.

It was initially thought that the girls had escaped, but two days later, their whereabouts are still not known.

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

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The latest attack was in Dapchi, Yobe state, about 275 km (170 miles) north-west of Chibok.

Locals living near the school told the BBC that about half the girls who had fled have been found after hiding in surrounding villages – some up to 30 km away.

“Eight hundred and fifteen students returned to the school and were visibly seen, out of 926 in the school. The rest are missing,” the police minister of Yobe state, Abdulmaliki Sumonu, told reporters.

But Mr Sumonu added that “no case of abduction has so far been established.”

Officials are not calling this a kidnapping, and say many of the girls and teachers ran into the bush and may still be found.

The father of one 16-year-old girl told the AFP news agency: ” We still don’t know how many of our daughters were recovered and how many are still missing. We have been hearing many numbers, between 67 and 94.”

One parent told the BBC they had seen a truck full of students being taken away.

The security services are said to be combing the surrounding area to find the missing girls.

Some residents and civilian militia in Dapchi said they believed the jihadists had planned to kidnap schoolgirls in their town too, AFP reports.

The jihadists came into the town, firing guns and letting off explosives, causing students and teachers to flee into the surrounding bush.

Residents say that Nigeria’s security forces – backed by military jets – later repelled the attack.

The school has been shut, and is being guarded by troops.

What has happened to the Chibok girls?

Last September, a group of more than 100 of the Chibok girls were reunited with their families at a party in Abuja.

Most of the group were released in May as part of a controversial prisoner swap deal with the Nigerian government that saw five Boko Haram commanders released.

But more than 100 schoolgirls are still being held by Boko Haram, and their whereabouts are unknown.

Boko Haram militants have been fighting a long insurgency in their quest for an Islamic state in northern Nigeria. The conflict is estimated to have killed tens of thousands of people.

The Chibok girls represent a fraction of the women captured by the militant group, which has kidnapped thousands during its eight-year insurgency in northern Nigeria.

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