Seventy-six of the 110 schoolgirls whom militants abducted from their boarding school on February 19 were "dropped off" early Wednesday in Dapchi in northeast Nigeria, the country's minister of information and culture, Alhaji Lai Mohammed, said in a statement.
The release of the students was ongoing, and the number of freed girls will be updated after the remaining ones are documented, the statement said.
Boko Haram fighters abducted the 110 girls from the Government Girls Science and Technical College in Dapchi on February 19.
In the statement, the information and culture minister said the 76 students had been released following "back channel efforts" by the government.
The minister said the release was unconditional. "The government had a clear understanding that violence and confrontation would not be the way out as it could endanger the lives of the girls," he said in the statement.
Kachalla Bukar, the secretary of the missing girls parents' association, told CNN the girls were seen walking into Dapchi at about 7:30 a.m. local time.
Bukar said he saw around 50 of the girls but had not seen his 14-year-old daughter, Aisha, who also was captured in last month's raid.
"The girls said Boko Haram dropped them about 20 kilometers into Dapchi town and told them to find their way," he said. "... Parents are rejoicing here, but we can see they have suffered."
Parents were heading into town for a head count and confirmation of numbers, Bukar said.
The mass kidnapping brought back painful memories of the 2014 Boko Haram abduction of nearly 300 girls from a separate school in Chibok, 170 miles southeast of Dapchi. More than 100 of them remain in captivity.
Nigerian President Muhammadu Buhari has described the kidnappings in Dapchi as a "national disaster" and deployed troops and surveillance aircraft in search of the missing students.
"Let me assure that our gallant armed forces will locate and safely return all the missing girls,"Buhari said in a statement on Twitter in February.
But an Amnesty International report on the kidnappings released this week accused the Nigerian army of failing to act on advance warnings of the raid.
According to the report, at least five phone calls were allegedly made to the army and police on the afternoon of the attack, warning the Boko Haram militants were on their way to the school.
"The Nigerian authorities must investigate the inexcusable security lapses that allowed this abduction to take place without any tangible attempt to prevent it," said Osai Ojigho, Amnesty International's Nigeria Director.
Nigerian army spokesman John Agim told CNN the allegations weren't true and the army had not been informed.