Amnesty International has accused "all sides" in the war in eastern Ukraine of showing a "disregard for civilian lives." The rights group said Sunday that both Ukraine forces and Russia, with its alleged support for pro-Russian rebels there, were "violating international obligations."

"Our evidence shows that Russia is fueling the conflict, both through direct interference and by supporting the separatists in the East," Amnesty Secretary General Salil Shetty said in a report published on Sunday.

"Russia must stop the steady flow of weapons and other support to an insurgent force heavily implicated in gross human rights violations."

The report said there was "compelling evidence" to prove Russia's involvement in the conflict.

The London-based rights group also said there was enough evidence provided by civilians to indicated abductions, torture and killings.

"Their testimonies suggest that the attacks were indiscriminate and may amount to war crimes," the secretary general added.

"Civilians in Ukraine deserve protection and justice … without a thorough and independent investigation, there's a real risk Ukrainians will harbor the scars of this war for generations."

Ceasefire broken

The statement was published not long after witnesses in the eastern harbor city of Mariupol reported explosions and artillery fire.

A ceasefire between rebels and Ukrainian forces had been agreed in the Belarusian capital of Minsk on Friday evening. Many people in eastern Ukraine and observers in the West, however, regard the ceasefire as a farce. Both the EU and the US have prepared tougher sanctions for Russia should fighting continue.

According to United Nations figures, over 2,500 people have died in the conflict since mid-April.

sb/av (AFP, dpa)