Half of the girls abducted from the school in Chibok, Nigeria on April 14, 2014 remain in captivity – but parents whose children have returned won't be celebrating until they are all free.

Chibok parents spokeswoman Yakubu Nkeki Maina, whose daughter returned, told Open Doors: 'We are still in pain. Though some of our daughters are back we cannot celebrate their return in the presence of our colleagues whose daughters are still missing. It will be like a provocation to our brothers and sisters. We must bear the cross together and keep the faith and hope that God gives us a reason to celebrate together when all the daughters are back.'

Of the 275 girls who had gathered to take an exam, 230 were kidnapped by the Islamist Boko Haram group. It is believed some have died while others have been forcibly 'married' to their captors.

For Pastor Ayuba Muta and his family, the rescues have been bittersweet, says Open Doors. Two of his daughters were kidnapped. One was released, one remains in captivity.

'By the time I heard the news that my daughters were kidnapped, I became so worried thinking I would no longer see these girls,' Pastor Ayuba said. 'Open Doors counselled us for some time, and I felt very comforted. I began to surrender all things to God. Then one day I learned that one of my daughters was released, while the other one is still there. What is impossible with man is possible with God. I trust God that one day my other daughter also will be released.'

Open Doors has conducted trauma counselling and provided financial support for medication and food for the girls and their families. The town is recovering after the abduction and the school itself is being renovated and extended.

An Open Doors partner who visited said: 'We left Chibok encouraged over the testimony of the Chibok parents and the difference we can see our presence has made for them. But we also felt deeply burdened by the desperate need for continued encouragement and prayer we observed. Therefore, we want to ask our family around the world to again rally around these parents through prayer and encouragement until they have been reunited with their daughters.'