Nigerian parents waited anxiously Sunday outside the school their daughters were taken from, amid rumors of their release and heavy security.
The 317 schoolgirls, ages 12-16, were kidnapped Friday from the Government Girls Science Secondary School in the town of Jangebe by armed men.
The state government has called the rumors a "falsehood." Nigeria's army has been working through the weekend alongside Zamfara state police in a search and rescue operation.
Nigerian President Muhammadu Buhari said his priority is ensuring the safe return of all hostages. Buhari urged state governments Friday not to negotiate with bandits by paying ransom with money or vehicles.
Hundreds of Nigerian schoolgirls were infamously kidnapped by the extremist group Boko Haram in 2014. Known as the Chibok girls, they were taken from their boarding school. In the seven years since, many of the 276 girls have escaped, been rescued or released, but more than 100 remain missing.
Since then, Nigeria has seen several such kidnappings. As recently as Saturday, 24 students were released after having been abducted February 17 from the neighboring nation of Niger.
The U.N. condemned the abduction over the weekend, calling it a "heinous violation of human rights."
"The girls must be released to their families immediately & unconditionally," Secretary General Antonio Guterres wrote on Twitter.
Kidnappings have been carried out by Boko Haram and the Islamic State in West Africa, but other militant groups with unclear motivations have also adopted the practice as a way to raise money. Boko Haram opposes Western education and has frequently targeted schools.