Two Kenyan police officers have pleaded not guilty to kidnapping two Ethiopian rebels in the capital, Nairobi.
Painito Bera Ng’ang’ai and James Ngaparini are alleged to have driven to the Ethiopian border and handed them over to Ethiopian officials.
The abducted men are from a splinter group of the Ogaden National Liberation Front (ONLF), fighting for independence for the Somali-speaking Ogaden region.
They were in Kenya to facilitate peace talks with the Ethiopian government.
Correspondents say their abduction on 26 January is threatening to scupper the next round of talks.
Sulub Abdi Ahmed and Ali Ahmed Hussein are senior negotiators for the ONLF in the talks being brokered by the Kenyan government.
The ONLF told the BBC Somali Service that it believed the Ethiopian government was behind their kidnapping.
But Abdinur Abdullahi Farah, a security adviser to the president of the Somali region, as the Ogaden is officially known, told US VOA radio that the men had given themselves up voluntarily.
Rebels in the Ogaden region have been fighting for independence since the 1970s and the ONLF has been at the forefront of the fight since it was founded in 1984.
The Ogaden is an ethnic Somali part of Ethiopia.
One ONLF faction has signed a peace deal with the government, but another has continued to fight the army.