Several chiefs of the Prosecutor General's office vowed to bring the people behind the killings to justice. The latest of them, Mr. Yuriy Lutsenko recently said ‘he couldn't imagine the investigation would take years, Ukraine Today reports.

Ukrainian lawyer Markiyan Halabala, involved in the case, says there has been some progress on the investigation, although much more could be achieved in this time.

"One of the titushka [hooligan] leaders, said he received information on February 18, that there would be shooting on the Euromaidan activists. This evidence is very helpful for us and it can explain that shooting of the protesters was kind of planned, it wasn't just a reaction from the Berkut units," Mr. Halabala said, saying the source of the information is kept secret.

Several Berkut officers are on trial for their reported involvement in the shooting. One of them, Viktor Shapovalov partially admitted his guilt and pointed at colleagues, who were given pump-action shotguns during the protests, instead of rubber bullets. Some officers were also paid extra for their activities, Halabala said.

It remains difficult, though, to legally prove where the money and orders came from.

"It's a problem, when we go much higher it's hard to get evidence who had given the orders. We know, that the orders were given by Ukraine's highest-ranking officials at the time, Zakharchenko (former Interior Minister), Yanukovych and so on, but we are working to get the evidence," Halabala said.

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