United Nations, Aug 4 (IANS): UN Secretary-General Antonio Guterres has said that he will set up a fact-finding mission to look into the recent attack on a Donetsk prison in Ukraine that reportedly killed dozens of prisoners of war.

He has received requests from both Russia and Ukraine for an investigation into the shelling of the prison in Olenivka, Guterres told reporters on Wednesday.

"I decided, in line with my own competencies and powers, to launch a fact-finding mission -- I have not the authority to do criminal investigations, but (have the authority) to launch a fact-finding mission," he was quoted as saying by Xinhua news agency.

The terms of reference for that fact-finding mission are being prepared at the moment. They will be shared with the governments of Russia and Ukraine, he said. "I hope we will be able to have an agreement on the terms of reference of that mission."

At the same time, the world body is recruiting "competent, independent people" for the fact-finding mission and is engaged in heavy coordination work, he said.

"We hope to have the facilities from both sides for access and for the obtention of all data that is necessary to be able to clarify the truth about what has happened," said Guterres. "This is a matter that we took very seriously and we are working hard for that."

Ukraine and Russia accused each other of carrying out the fatal attack on the prison in Olenivka.