Since Crimea voted in a referendum to join Russia last month, tensions have continued to rise in the rest of Ukraine. On Sunday, pro-Russian activists in the east of the country -- home to a vocal pro-Moscow separatist movement -- occupied government buildings in three major cities: Donetsk, Luhansk and Kharkiv. The activists each demanded a referendum on cutting their ties with Ukraine, similar to the one held in Crimea.
The activists' moves put the Ukrainian government in Kiev in a tough spot. While Kiev is opposed to the protesters' demands, it fears that Moscow will use any report of violence against the activists as a pretext to invade. In an effort to dissolve the crisis, Ukraine's Interim Prime Minister Arseniy Yatsenyuk pledged on Friday that the national government will hand over some of its powers to the regions.
Ukraine's eastern regions are linguistically and culturally close to their Russian neighbor, and many of their residents distrust the national government that took power after President Viktor Yanukovych was ousted. In addition, the regions have close economic ties with Russia and fear Kiev's overtures to Europe will negatively affect their industries. Yet while pro-separatist gunmen have grabbed attention, polls show that popular support for independence is not strong in all of Ukraine's east, according to The Financial Times.
However, as the BBC's Steve Rosenberg notes: "Small numbers can achieve big things when there is a power vacuum."
See below for profiles of the three regions in eastern Ukraine where protesters are demanding autonomy from Kiev.
Armed, pro-Russian protesters have occupied the local office of Ukraine's security service in Luhansk since Sunday, despite efforts by the authorities to force them out by cutting water and electricity. Luhansk residents supportive of the pro-Russian effort blockaded streets and built makeshift barricades to protect the activists. Radio Free Europe reported that some of the gunmen claimed to be former members of Berkut, the Ukrainian riot police force that was disbanded after it was blamed for civilian deaths during the anti-Yanukovych protests.
Luhansk's economy largely depends on Russia and many of the region's residents are therefore wary of Kiev's rapprochement to the European Union. As the BBC explains, pro-European residents are a minority in the city.
Pro-Russian activists guard the entrance of the regional Security Service building in the eastern Ukrainian city of Luhansk on April 9, 2014. (GENYA SAVILOV/AFP/Getty Images)
Pro-Russian activists stand outside the regional security service building in the eastern Ukrainian city of Luhansk on April 10, 2014. (GENYA SAVILOV/AFP/Getty Images)
Pro-Russian activists reinforce their barricade at the regional security service building in the eastern Ukrainian city of Luhansk on April 10, 2014. (GENYA SAVILOV/AFP/Getty Images)
Separatists seized the regional government building in Donetsk on Sunday and declared the Donetsk region an autonomous republic.
The home of former President Yanukovych, Donetsk is a coal-mining region with strong ties to Russia. While some residents insist the separatist gunmen do not represent their views, many of the region's residents say Kiev does not support the economy enough or adequately protect Russian speakers from right-wing radicals.
A woman wrapped in a Russian national flag walks in front of a barricade at the regional administration building in Donetsk, April 9, 2014. (AP Photo/Alexander Ermochenko)
A pro-Russian militant guards a barricade in front of the Donetsk regional administration building on April 8, 2014. (ALEXANDER KHUDOTEPLY/AFP/Getty Images)
Pro-Russian activists shout during a rally at the regional administration building in Donetsk, April 8, 2014, (AP Photo/Efrem Lukatsky)
Pro-Russian protesters also stormed Kharkiv's regional administration building on Sunday, but were later forced out by Ukrainian security forces. While dozens were arrested on separatism charges, pro-Russia activists continued to rally in the city, according to The Kyiv Post.
Kharkiv is Ukraine's second-largest city and home to pro-Kiev and pro-Moscow activists, which have staged rival rallies throughout the country's recent turmoil. Kharkiv's leadership also exhibits the multiple loyalties of the predominantly Russian-speaking city -- pro-Russia officials fled the city when Yanukovych fell only to return and switch allegiance to Kiev.
A pro-Russian activist holds a sign reading 'Kharkiv is a Russian city !' during a rally at the regional administration building in Kharkiv, April 7, 2014. (SERGEY BOBOK/AFP/Getty Images)
Activists hold Ukrainian flags during a rally in front of pro-Russian activists at the regional administration building in Kharkiv, April 7, 2014. (SERGEY BOBOK/AFP/Getty Images)
Ukrainian policemen stand guard in front of the Kharkiv regional state administration building on April 8, 2014. (ANATOLIY STEPANOV/AFP/Getty Images)