Dissident rebels have released 36 members of an African Union team, including an American monitor, who were kidnapped in Sudan's powder keg western Darfur region, an AU spokesman said on Monday.
Two members of the AU team, its Senegalese leader and a translator still were being held, said Nourdin Mezene, spokesman for the African Union in Khartoum.
"We are doing our level best now to secure their release, " Mezene said, adding that 36 were set free late Sunday.
The AU military high commander has gone to the Tine region in west Darfur, near the border with Chad, to negotiate the release of the two remaining captives, Mezene said.
The abductions occurred 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 AU was to hold an emergency session later Monday to discuss the deteriorating security situation in Darfur, the organization's top envoy to Darfur said.
The meeting will try and find ways of preventing renewed violence in Darfur spiraling out of control, Baba Gana Kingibe told The Associated Press.
"The international community should be very alarmed by these events because the situation is getting out of hand and we are sliding backwards," Kingibe said ahead of the meeting.
The Sudanese government has condemned the abduction and killing of members of the African Union Mission in Sudan but said it was up to the AU to stop the attacks. Khartoum also called on the international community to pressure rebels in Darfur to abide by a cease-fire agreement signed with the government.
The government said it was committed to continuing negotiations to find a comprehensive solution to the crisis n the western region.
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 violence began after rebels took up arms against government forces against for what it regarded as years of state neglect. Sudanese authorities are accused of subsequently unleashing militias known as the Janjaweed against the rebels and fanning a conflict that has sparked what the U.N. has described as the world's worst humanitarian crisis.