Dozens may have been killed in the violence. Although the US government generally condemns a countrys use of military force against its own population, especially if they are unarmed protesters, this time the US administration blamed the victims. After as many as 20 unarmed protesters were killed on the May 9th holiday in Ukraine, the State Department spokesman said "we condemn the outbreak of violence caused by pro-Russia separatists."
Why are people protesting in eastern Ukraine? Because they do not believe the government that came to power after the US-backed uprising in February is legitimate. They do not recognize the authority of an unelected president and prime minister.