Vienna, Nov 20 (IANS /TASS): More than 4,000 people have been killed and tens of thousands of people have been injured in the conflict in eastern Ukraine, the special envoy of the Organisation for Security and Cooperation in Europe (OSCE) said Thursday.

Hundreds of thousands of people have been forced to leave the war-hit region, OSCE chairperson Heidi Tagliavini told a session of the OSCE Permanent Council, adding that the prospects of settling the crisis were rather "clouded".

The crisis remained very dangerous both for the stability of the region and for Europe, she said.

Over the past two days, Ukrainian troops have opened fire at monitors from the OSCE twice, the Special Monitoring Mission (SMM) said in a report Wednesday.

The Kiev authorities launched a military operation in mid-April against pro-Russian independence-seeking militias in eastern Ukraine’s Donetsk and Lugansk regions to regain control over the territories.

The parties to the Ukrainian conflict agreed on a ceasefire at talks mediated by the OSCE Sep 5 in Belarusian capital Minsk. The ceasefire took effect the same day but has reportedly occasionally been violated.