(CNN) -- Three employees of the International Committee of the Red Cross who were seized by armed tribesmen in southern Yemen on Monday have been released, the ICRC in Yemen said Thursday.
The three, who were kidnapped while working in Abyan province, are now back in the port city of Aden, an ICRC statement said.
"We are relieved and extremely happy to have our colleagues back with us," said Cedric Schweizer, who heads the ICRC delegation in Yemen.
"We would like to thank all those who gave us their support unconditionally with the aim of getting our colleagues back safe and sound."
The three staff members, who were returning from a field trip in an ICRC-marked vehicle, were stopped by armed men Monday morning near Ja'ar, the ICRC said.
The ICRC has been working in Yemen since 1962, it says, providing aid for civilians affected by conflicts.
Current projects include delivering aid, upgrading water supply systems and providing medical equipment and drugs for health care facilities, as well as supporting detainees and their families.
The ICRC currently has more than 200 staff, including about 50 international employees, working in Sana'a, Aden, Sa'ada, Amran and Taiz.
Security officials who spoke to CNN Monday described the kidnappers as militants who had problems with the Yemeni government. They did not believe the gunmen were linked to al Qaeda, which has members and sympathizers in Yemen.
The latest incident came only days after armed tribesmen in Abyan kidnapped two Egyptians and two Indians.
Last week, a Finnish couple and an Austrian kidnapped in December were released by suspected al Qaeda militants after receiving a ransom.
CNN's Hakim Almasmari contributed to this report.