A cameraman for Russia's state-owned Channel One television has been killed in Ukraine's eastern Donetsk region, the channel has said.

Anatoly Klyan, 68, was shot in the stomach when his film crew came under fire overnight after they went to film near a pro-Kiev military unit in the region, the channel said on its website on Monday. The trip was organised by pro-Russia rebels.

The statement said the journalists were accompanying a group of soldiers' mothers who were being driven to the unit "to meet their sons and take them home".

The bus carrying the mothers and the journalists withdrew after coming under fire as it approached the base.

Klyan died when a group of people came under further automatic rifle fire after leaving the bus, the channel said.

Russia has protested against the killings of its journalists, calling on Kiev to stop operations in Donetsk and

the region of Luhansk, where separatists have seized state buildings and weapons arsenals.

On June 17, a Russian correspondent and a sound engineer for state television were killed by mortar fire in clashes near Luhansk.

Sporadic violence has continued in eastern Ukraine despite a cease-fire declared by Petro Poroshenko, Ukraine's president, on June 20 to allow for peace talks with the rebels. The ceasefire is due to expire on Monday 1900GMT.