Save the Children has said it will “leave no stone unturned” as it investigates how a UK nurse caught Ebola while working with the charity in Sierra Leone.

Pauline Cafferkey, from South Lanarkshire, fell ill following her return to Glasgow a week ago and is currently in a critical condition in a north London hospital.

Rob MacGillivray, Save the Children's Sierra Leone director, told the BBC the charity would carry out a special investigation over and above its routine reviews.

He said: "Because of this very serious event we have put in an extraordinary review to ensure that we do everything, leave no stone unturned, to be able to as far as possible identify the source of this infection."

MacGillivray went on to say that the investigation would look at how protective equipment is used, and at person-to-person contact both inside and outside the Kerrytown treatment centre where the nurse worked.

Save the Children has said it has been conducting a review since Cafferkey was confirmed as Ebola positive. The Serious Event Review is looking at how she may have contracted Ebola by reviewing training, safety protocols, how protective equipment is used, and working practices.

The findings of the review will be considered by a panel including independent health experts, which will support Save the Children and make recommendations for any action if necessary. The early findings of the review will be made available by Save the Children as soon as possible.