Updated

A Nigerian official says more of the Chibok schoolgirls have been released three years after their abduction by Boko Haram extremists, though the exact number is not immediately known.

The official spoke on condition of anonymity late Saturday because they were not authorized to speak to reporters.

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.