A young woman, who gave birth in detention three months ago, is among the group of women, children, elders and young men who were freed.

It is unclear when she was arrested but some of those freed have been in military custody since 2010, when the militants launched a full-scale insurgency in the north-east to establish its version of Islamic rule.

A total of 205 people have so far been convicted in the mass trials.

They include a man identified as the mastermind of the abduction of 276 schoolgirls in the town of Chibok in 2014, judicial sources have told the BBC.

Haruna Yahaya, 35, was sentenced to 15 years in prison on Friday for masterminding the abductions, which caused global outrage.This is in addition to a 15-year sentence he received earlier for taking part in the kidnappings.

The judge ordered Yahaya to spend 30 years in prison.