Ukraine Mariupol women police station fire
Two women walk in front of the burned police headquarters in the southeastern port city of Mariupol, UkraineReuters

As gunfire continues in eastern Ukraine, United Nations Assistant Secretary General for Human Rights Ivan Simonovic has delivered a gloomy assessment of the region's future.

Simonovic, who was born in Croatia, says the Ukraine is reaching "the point of no return" and could even spiral into the sort of ethnic bloodshed witnessed in the Balkans in the 1990s following the break-up of the former Yugoslavia.

Speaking to the BBC, Simonovic said around 250 people have already died in the fighting between those loyal to Kiev and pro-Russian factions wishing to break away and form their own autonomous republics.

"What I am really afraid is that the country is reaching the point of no return, if there is no adequate and urgent action taken. We already estimate that some 250 people have died - in the eastern part of the country 127, but recently we had a terrible disaster, a terrible tragedy that has taken place in Odessa, which was the largest incident with 48 people killed, with a lot of question marks, with police not reacting promptly or decisively. This requires thorough impartial investigation."

Ukraine referendum
Members of a local election commission sort ballots as they start counting votes of the referendum on the status of Luhansk regionReuters

Despite this bleak assessment, Simonovic said he was not in a position to call the conflict a civil war. It was the responsibility of the International Committee of the Red Cross (ICRC) to classify fighting as an internal armed conflict and so far the ICRC has not done so. Simonovic's own country, Croatia, was embroiled in a bloody civil war in the 1990s also involving Serbia and Bosnia. Now, he said, there is a chance Ukraine could go the same way.

"In former Yugoslavia it took over 100,000 victims to reach political settlement. Can't we reach political settlement in Ukraine without such a heavy toll?"

Last week's unofficial referendums led to the installation of "people's republics" in Donetsk and Luhansk, but abduction, torture and murder continue. A nationwide election will take place on 25 May. Asked whether he believes a united Ukraine was still possible, Simonovic said: "I firmly believe there is a window of opportunity that should be used - but the window is closing."