Russian militia

We are talking about the "partisans" who also published videos of their fighters in armored vehicles at the border crossing of Grayvoron, which separates Ukraine from Russia.

Around 75,000 troops will be deployed around Ukraine to ensure security in Sunday's presidential elections.

It is still unclear how many polling stations will be opened in the eastern part of the country, where pro-Russian militia still keep tight control.

Clashes between pro-Russian federalists and Ukrainian troops have reportedly led to a number of casualties in the eastern city of Slaviansk on Monday.

NATO Secretary-General Anders Fogh Rasmussen has announced plans to "immediately" bolster collective defense at the alliance's eastern flank.

Forces "at sea, in the air, on land" are to be rapidly deployed in response to the continued Ukrainian-Russian  standoff, The Guardian quoted him as saying.