A Kenyan Christian teacher has been rescued from al-Shabaab after being kidnapped by the Islamist militant group last week.

Judy Mutua was rescued by the Kenya Defence Forces and Somalia National Army in Somalia on Friday following a shootout with members of al-Shabaab, the Defence ministry said in a statement.

"Ms Mutua is currently receiving treatment at a secured location and will be airlifted by the Kenya Air Force to Nairobi in the course of the day," the statement added.

One abductor was killed during the rescue operation, and another arrested. Four managed to escape with gunshot wounds, KDF regional coordinator Mohamud Saleh told reporters.

In an interview with Kenyan newspaper The Star, he said the Kenyan military "will not rest until all the culprits are brought to book".

Mutua had been abducted in Garissa county, Kenya on October 12. A teacher for the NGO Windle Trust International, the vehicle she was travelling in was attacked as she travelled between two refugee camps.

Al-Shabaab is particularly active in the northeast of Kenya where the Muslim population is more concentrated.

In April, 148 students at Garissa University College were killed by the terrorist group, forcing many schools in Kenya to close after teachers – afraid of further attacks – refused to work.