Dissident rebels kidnapped a group of African Union personnel and an American monitor in Sudan's powder keg western Darfur region, officials said, but some of the hostages were later released.
The abductions near Sudan's western border with Chad on Sunday came a day after two African Union troops were killed by another rebel group the first fatalities suffered by the pan-African body since it deployed peacekeepers to Darfur in April 2004.
The rebel killings and kidnappings have been condemned by the African Union, which has described them as major violations of a shaky cease-fire deal aimed at ending the Darfur conflict that started in 2003 and has claimed the lives of more than 180,000 people.
The Ethiopian-based AU is expected to discuss the incidents at an emergency meeting Monday.
Eighteen AU members and one American were taken hostage by a faction from one of two main Darfur rebel groups, the Justice and Equality Movement, said an AU official who declined to be identified further as he was not authorized to speak to the media.
It was unclear if the American was among those released nor what his exact role was, but he may have been a monitor working with the African Union, said Elizabeth Lukasavich, a spokeswoman for USAID in the Sudanese capital, Khartoum.
"Some people have been released but we don't know who," Lukasavich said. "The American may have been an observer or a contractor. There are quite a lot of Americans out there working as observers with the African Union troops," reports the AP.