The International Committee of the Red Cross (ICRC) confirmed that a Swiss staff member was killed on Thursday by a shell that landed close to its office in Donetsk, eastern Ukraine.

"One of our colleagues, a Swiss national, was killed in Donetsk, Ukraine, when a shell hit close to our office. We're deeply distressed by this loss," ICRC spokesman Ewan Watson told Reuters.

The independent aid agency was still trying to piece together what happened and was not disclosing the victim's name.