More than 300 girls were abducted on Friday from a school in Jangebe, in northwestern Nigeria.
It is the latest mass kidnapping in schools, an increasingly common event and for which armed gangs are demanding ransom.
The president, Muhammadu Buhari, condemned the kidnapping, calling it “inhuman and totally unacceptable”.
“This government will not succumb to the blackmail of bandits who choose innocent school children to raise large sums in ransom,” he said in a statement.
Buhari said the goal is for the girls to return alive and unharmed, noting that although authorities could use deadly force against the kidnappers, there is fear that the girls will be used as human shields.
At least 42 people, including 27 students, were kidnapped last week and have not yet been released.
The 2014 kidnapping of 276 schoolgirls by Islamist militants from Boko Haram It brought worldwide attention to the attacks on schools in Nigeria, but the most recent ones are suspected of being carried out by criminal gangs.
On Friday, witnesses told the BBC’s Hausa service, about 100 armed men entered the school.
A teacher told the BBC that of the 421 students in the school at the time, only 55 remained.
Neither group claimed responsibility for the attack.
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