A tearful reunion for Chibok girls: Could 83 more girls be released?

The 21 Chibok girls released by the terrorist group Boko Haram last week were reunited with their families on Sunday.

Parents tearfully celebrated their daughters' return home after more than two years of captivity. At a church service organized by the Nigerian government, many of the girls held up their Bibles in a symbolic gesture to refute their forced conversion to Islam under Boko Haram, CNN reported.

The emotional scene has brought hope back for many of the parents and loved ones of those who have not yet returned, as the government prepares to open negotiations for the release of 83 of the remaining girls.

"We thank God. I never thought I was going to see my daughter again but here she is," one parent told the BBC. "Those who are still out there – may God bring them back to be reunited with their parents."

In April 2014, more than 200 schoolgirls were kidnapped by the Nigerian terrorist group Boko Haram. Of those, 57 quickly escaped, and one was found last May at the outskirts of Nigeria's Sambisa Forest, the edge of the territory held by the group. Aside from occasional videos released by the militants, in which the girls are offered in trade for captured militants, very little has been seen of most of the captives since the original kidnapping.

On Sunday, the girls spoke of their ordeals, from a lack of food to dodging the bombs of airstrikes carried out by the Nigerian government against Boko Haram. But mostly, it was a day for celebration.

The release of the girls was unexpectedly announced last Thursday by the Nigerian government, which had previously said negotiations with the terrorist group had broken down. The release of the 21 Chibok girls was brokered by the Swiss government and the International Red Cross, though it is still unclear why the terrorist group let the girls go now. The Associated Press and BBC were both told by sources close to the negotiations that the girls were exchanged for four Boko Haram commanders, but the government has denied those claims. The government has also not confirmed reports that a large ransom was paid to the terrorist group.

"There was no exchange of any kind. There was no swap of any kind," Nigerian Vice President Yemi Osinbajo told reporters. "When we started negotiations, we said we would consider all options available to us. Absolutely, there was no exchange of any kind."

Boko Haram has faced infighting since the girls were kidnapped in 2014. In 2015, the group pledged itself to ISIS and changed its name to ISWAP (Islamic State West Africa Province). After the name change, ISIS appointed Abu Musab al-Barnawi as the leader of the group, but a separate faction continues to be led by Abubakar Shekau, the previously undisputed head of Boko Haram. Mr. Shekau's faction re-adopted the name Boko Haram, which currently holds most if not all, of the Chibok girls. Since then, the splintered group has continued to lose territory due to raids by the Nigerian military.

The Nigerian government has said that negotiations for 83 of the remaining girls will resume on Monday. Sources told CNN that the 114 other girls held by Boko Haram have died, been married off to their captors, or do not want to leave, which may include some who have been radicalized. If accurate, that would mean more than 40 percent of the Chibok girls may never return home. But for the 21 girls who have been released and for their families, hope for the remaining girls is at the strongest it has ever been since the kidnapping took place over two years ago.

"By God's grace she is back," Hawa Abana, the mother of one of the released girls, told Al Jazeera. "She will go back to school. Boko Haram has no power again."