More Chibok schoolgirls have been released three years after their abduction by Boko Haram extremists, though the exact number is not immediately known, Nigerian officials said.
Nearly 200 of the schoolgirls had remained captive before this release.
Many of the girls seized from their boarding school were forced into marriages with fighters and became pregnant.
Nigeria's government in October announced the first negotiated release of 21 of the schoolgirls.
At the time, it said another group of 83 girls would be released "very soon".
The government has denied a ransom was paid and that it freed some detained Boko Haram fighters in exchange for the girls.
Extremists from the group, meanwhile, are actively planning to kidnap western foreign workers in north-east Nigeria, according to the US and UK governments.
The extremists are said to be targeting foreigners in the Bama area of Borno state, close to the Cameroon border.
The Nigeria-based Boko Haram has been pushed out of strongholds by military efforts but continues to control parts of the country's north-east.