The family of a Christian missionary and doctor, who was held hostage for more than seven years by Islamic extremists, has given thanks to God as he is finally released.

Australian surgeon Kenneth Elliott, 88, and his wife Jocelyn had been running a free medical clinic in Djibo in northern Burkina Faso, providing surgery and healthcare to locals, when they were abducted by al-Qaeda militants in 2016.

Al-Qaeda in the Islamic Maghreb (AQIM) claimed responsibility for the kidnapping at the time.

The local Djibo community managed to secure Joyce's release after launching a public three-week freedom campaign.

Multiple calls for Ken’s release have been made since the abduction. On his thousandth day in captivity, Joyce expressed her gratitude for her own freedom and implored for her husband to be released as he “lives out his last years”.

In a statement to the Foreign Office, following his release, the Elliott family expressed their "thanks to God" and to those “who have continued to pray for us.”

“We express our relief that Dr Elliott is free and thank the Australian government and all who have been involved over time to secure his release. We also continue to pray for those still held and wish them freedom and safe return to their loved ones.

“At 88 years of age, and after many years away from home, Dr Elliott now needs time and privacy to rest and rebuild strength. We thank you for your understanding and sympathy.”

On the same day as Elliott’s abduction AQIM was also reported to have killed 29 people in Ouagadougou, including six Canadian Christians doing humanitarian work and a missionary from the US, according to anti-persecution charity Open Doors.

The charity, which ranks the countries where it is most dangerous to be Christian, states that the "expanding influence of jihadist groups in Burkina Faso is having a catastrophic impact on Christians" there, with many facing violence, death and the destruction of their churches and villages.