The team – seven Congolese and one Swiss national – was seized on Friday by
They had been returning from a mission to help displaced people in the area.
There has been instability and violent conflict in the east for almost two decades and the Red Cross is one of the few aid organisations working there.
The International Committee of the Red Cross said their staff were being held in the vicinity of Fizi in South Kivu where violent clashes in recent months had displaced thousands of civilians.
"We continue to insist that the strictly neutral, impartial and humanitarian nature of our work be recognised, and that our colleagues be able to return to their loved ones soon," Franz Rauchenstein, head of the ICRC’s Congolese delegation, said in a statement.
The UN has the world’s biggest peacekeeping mission in DR Congo, trying to stop fighting between armed groups.
The mission’s current mandate expires in May and the UN is in talks with DR Congo officials about withdrawing it.
Source: BBC