One of two aid workers kidnapped from a Somali town near the Ethiopian border is doing well, said a spokeswoman for their organization, Save the Children.

The British aid worker is “well,” said Anna Ford of Save the Children in Nairobi, Kenya. “He is being looked after and is in good spirits. We are still extremely concerned about him and call upon whoever is holding him to release him.”

The organization said gunmen kidnapped two aid workers, a Somali national and a Briton, earlier this week.

Ford said Save the Children is in contact with the aid worker’s family. She would not disclose how the organization was aware he is in good spirits. No details were available on the second aid worker.

The British Foreign Office has said it is investigating.

Save the Children is an international organization based in the United Kingdom. It works to improve the lives of children worldwide.

Somalia has not had a stable government since 1991, and fighting between rebels and government troops has escalated the humanitarian crisis in the famine-ravaged country.

“Save the Children was assessing the feasibility of starting up a humanitarian [program] to help malnourished and sick children and their families in the area,” the group said in a statement Friday. “We are extremely concerned about the welfare of those being held and urgently call upon whoever is holding them captive to release them unconditionally.”

— CNN’s Bharati Naik contributed to this report.