More than 80 schoolgirls kidnapped by Boko Haram three years ago have arrived in Nigeria's capital as part of a government prisoner exchange.
The office of Nigeria's president says Muhammadu Buhari is now leaving for London for a medical checkup as fears continue over the state of his health.
In response to a question, the source said: "Both parties agreed to manage the release of the girls in a no victor, no vanquished manner".
A global Bring Back Our Girls campaign, supported by former United States first lady Michelle Obama and other celebrities, has brought "tremendous pressure" on the Nigerian government to counter the extremist group, which controls large parts of the north of the country, says The Guardian. Now parents will know if they should make the journey to see their daughters.
Photos released by the government showed the rail-thin president standing and addressing the Chibok schoolgirls at his official residence Sunday evening, a day after their release.
The most high-profile attack took place on April 14, 2014, when Boko Haram kidnapped 276 schoolgirls from a secondary school in Chibok in northeast Borno state. At the time, the government denied making an exchange for Boko Haram suspects or paying ransom.
Adeyeye said "the suspected terrorists by this release have escaped justice", adding that "all the effort made by security agencies to bring them to book has come to nothing".
Last year, 21 other Chibok girls were liberated in October and they have been undergoing counseling for months.
She said government should do its best to see that the 82 freed girls were given full rehabilitation so that they can be reintegrated into the society.
Those girls are still in government care in Abuja for medical attention, trauma counseling and rehabilitation, according to the government. Human rights groups have criticized the decision to keep the girls in custody in Abuja, almost 900 kilometres (560 miles) from Chibok.
But Amnesty International objected to that meeting, saying the girls should be released quickly to their families and don't deserve to be put through a "publicity stunt that largely doesn't reckon with their privacy".
The ICRC along with the Swiss government had mediated months of negotiations between Nigeria and the Boko Haram extremist group to obtain Saturday's release.
It believed that with such exchange, the Boko Haram terrorists had been emboldened to continue their terror and kidnapping of innocent people.
The girls were among a group of 270 schoolgirls kidnapped in April 2014 by the militant group Boko Haram, which has waged an eight-year-old insurgency to create an Islamist caliphate, killing thousands and forcing more than two million from their homes. The brutality of the act sparked a global outcry, with the hashtag #BringBackOurGirls sweeping social media and unifying outraged citizens and political leaders alike, including then-first lady Michelle Obama.
Buhari late previous year announced Boko Haram had been "crushed", but the group continues to carry out attacks in northern Nigeria and neighboring countries. Its insurgency has killed more than 20,000 people and driven 2.6 million from their homes, with millions facing starvation.