Map: Kiev losing control of pro-Putin eastern Ukraine

Donetsk: Russian-speaking separatists say that the vast majority of voters backed autonomy in a May 11 referendum on secession. Many hope to follow Crimea's break from Ukraine in March and subsequent annexation by Russia. On May 1 in Donetsk, anti-government demonstrators took over the regional prosecutor's office. Upon occupying the building, protesters discarded the Ukrainian flag and replaced it with that of the "Donetsk People's Republic." Activists took control of the customs service building in Donetsk on April 30. The City Hall of the mining region's largest municipality had been occupied by pro-Russian groups since April 6.

Kharkiv: Kharkiv Mayor Gennady Kernes was “hit by a bullet in the back” on April 28 during an attack by unknown gunmen, officials said, adding that he was “fighting for his life” as doctors performed surgery on him. Ukrainian officials have not commented on who they suspect was behind the attack, but Kernes could have angered both sides. He first held a pro-Russian stance, but after the ouster of pro-Russian Ukrainian President Viktor Yanukovych, he changed his position to support the new Western-backed government in Kyiv. Clashes in the city, more populous and geographically farther northwest than the other locales of violence, began around April 6. Pro-Russian forces have reportedly occupied and reoccupied government buildings several times.

Luhansk: Pro-Russian leaders declared independence in Luhansk after the May 11 autonomy vote, and announced the possibility of a second poll on whether to join Russia. On April 29, pro-Russian separatists had seized the main government buildings in Luhansk, capital of Ukraine's easternmost province — driving home just how far control over the densely populated region had slipped from the central government in Kyiv. On April 6, pro-Russian separatists had conducted a siege of Luhansk’s security services headquarters, as the radicals took some 60 hostages.

Slovyansk: Two Ukrainian helicopters were shot down and two of their crew members killed on May 2 in Slovyansk. A pro-Russian militiaman was reportedly killed in a separate incident there, according to The Associated Press. The Ukrainian Security Service said one of the helicopters was shot down with a surface-to-air missile, which it said undercut Russia's claims that the city is in the control of civilians who took up arms. Meanwhile, the Kremlin sent an envoy to Ukraine's southeast to negotiate, successfully, the release of seven military observers from the Organization for Security and Cooperation in Europe who had been captured by pro-Russian militias in Slovyansk.