A Red Cross worker has been killed in eastern Ukraine as a shell landed near the group's office in Donetsk, one of the main strongholds for pro-Russian rebel.

The International Committee of the Red Cross, (ICRC) identified the victim as Laurent DuPasquier, a 38-year-old Swiss national who had arrived in Ukraine just six weeks ago.

In a statement, Dominik Stillhart, the Geneva-based organization's director of operations, condemned the incident, saying "indiscriminate shelling of residential areas is unacceptable and violates international humanitarian law."

Government forces and the pro-Russian rebels blamed each other for the October 2 shelling.

Ukrainian Foreign Minister Pavel Klimkin wondered whether the "terrorists have any idea of what humanity is all about when they shell the Donetsk office of the ICRC, whose only aim is to help people?"

Rebel leader Andrei Purgin, in turn, said the Ukrainian government forces shelled Donetsk constantly and that the attack had come from one of their areas.

The incident comes as a cease-fire was announced September 5.