The BBC has learned that hundreds of high school students have been kidnapped in Zamfara State, northwest Nigeria.
A local teacher said that at least 300 female students were taken away in the Friday morning attack from the school where he worked.
A spokesman for the state governor confirmed the kidnapping, but gave no details.
The attack took place on Friday at 12 p.m. GMT, when gunmen on board pick-up vehicles and motorcycles stormed a government secondary school for girls in the Gangibi area in Zamfara state, according to a teacher testimony on a local website.
The teacher said that some of the gunmen were dressed as government security personnel, and that they drove the girls into the vehicles.
The BBC correspondent in the capital Abuja said that the families of the kidnapped girls had gathered in front of the school and that some of them went to look for the girls.
A teacher told the BBC that only 55 of the 421 students at the school were counted, meaning more than 300 may have been kidnapped.
This is the latest mass kidnapping operation targeting schools in recent weeks. Schoolgirls are usually kidnapped by gunmen for ransom.
Last December, Zamfra State also witnessed the release of 344 students, a week after they were kidnapped.
Boko Haram claimed responsibility for the kidnapping, but Nigerian officials deny this.
The government said at the time that it had not paid a ransom and that the boys were released after three rounds of negotiations with the kidnappers.
Boko Haram has been notorious for its schoolchildren’s kidnappings over the past decade, including one in 2014, when the group kidnapped nearly 300 schoolchildren from their school.
However, kidnappings were not uncommon in areas of north-eastern Nigeria, where Boko Haram is based.
As for the northwestern regions of Nigeria, armed attacks and kidnappings are often accused of bandits and gangs in the region.
What do we know about Boko Haram?
The name “Boko Haram” when translated means: “Western education is forbidden.”
Since its founding in 2002, Boko Haram has aspired to overthrow the government of Nigeria and establish an Islamic caliphate.
In 2009, Boko Haram carried out a series of attacks on police stations and other government buildings in Borno State, northeastern Nigeria, killing hundreds.
The group prohibits Muslims from participating in any political or social activity similar to the activities of Western society.
In 2003 Washington designated Boko Haram a terrorist organization.
In April 2014, Boko Haram faced international condemnation after it kidnapped more than 200 schoolgirls from Chibok, Borno State, saying it would treat them as slaves and war spoils.
Later, Boko Haram declared its allegiance to the Islamic State and turned its back on Al Qaeda.
Boko Haram’s activity extends beyond Nigeria’s borders to Cameroon, Niger and Chad, in violence that has killed tens of thousands of people and displaced millions of others.