Gunmen seized more than 100 students from a boarding school in northwestern Nigeria on Monday. A school official told the Agence France-Presse news agency the number of students abducted was 140.
"The kidnappers took away 140 students, only 25 students escaped. We still have no idea where the students were taken," Emmanuel Paul, a teacher at the Bethel Baptist High School in Kaduna state where the kidnapping happened, said.
Gunmen scaled a fence to break into the school in the early hours of Monday morning, kidnapping most of the 165 pupils boarding there.
Kaduna state police spokesman Mohammed Jalige confirmed to AFP the attack took place early Monday morning, but could not give details on the number students taken.
"Tactical police teams went after the kidnappers," he said. "We are still on the rescue mission," he added.
Wave of kidnappings in northern Nigeria
Monday's attack would be the fourth large-scale school kidnapping in Kaduna state since December.
Authorities have attributed previous kidnappings to bandits seeking ransom payments.
Criminal gangs often loot villages, steal cattle and carry out abductions for ransom in northwest and central Nigeria. However, since the start of the year, bandits have increasingly targeted schools and colleges.
It is estimated more than 800 students have been abducted since December in northern Nigeria. At least 150 remain missing.