The US State Department has released photos purportedly showing the presence of Russian soldiers in Eastern Ukraine.

According to US officials, the photos prove that some of the fighters taking part in Ukraine's recent unrest are actually special forces from Russia and even seemed to have Russian insignia, CNN has reported.

Ukrainian government representatives have claimed the 'evidence' is authentic and have argued that "sabotage-reconnaissance groups" are acting in the east.

They have even compared it to photos of Russian soldiers in Crimea this year and in Georgia in 2008.

Russia has so far not commented on the photographs, but has refuted claims that it is involved in the takeover of government buildings in at least nine towns and cities across the territory of its western neighbor.

It however acknowledged last week that it had military presence in Crimea weeks before a local referendum lead to the peninsula's incorporation into Russia.

NATO has repeatedly described Ukraine's fresh unrest as a Russian scenario, with Commander Gen. Philip Breedlove describing activity by separatists in the east and south as "a well-planned and organized" operation orchestrated by Moscow.

US representatives accused Russia on Tuesday of violating April 17's Geneva accord by fomenting tensions in regions near Ukraine's eastern border.

Moscow, on the other hand, holds firm that the US has supported the Maidan revolution that led to toppling President Viktor Yanukovych.

Late on Monday Russian media quoted US Assistant State Secretary Victoria Nuland as saying that her country had provided USD 5 B to Ukraine after the USSR disintegrated in 1991.

In the interview for CNN, Nuland insists the money was dedicated to stabilizing the country and helping to build a strong state.