U.N. Secretary-General Antonio Guterres said on Wednesday he will launch a fact-finding mission into an attack in the front-line Ukranian town of Olenivka that killed prisoners held by Moscow-backed separatists.
Russia and Ukraine both requested an investigation, Guterres told reporters. He said the terms of reference for the mission, which would need agreement from Russia and Ukraine, were being prepared.
(Reporting by Michelle Nichols; Editing by Rami Ayyub)
