Thirty pro-Russia insurgents and four government troops have been killed during operations to expunge anti-government forces around a key eastern city, Ukraine's interior minister reported Tuesday.
In the southwest, Kyiv authorities also attempted to reassert control over the key Black Sea region of Odessa by appointing a new governor there.
Interior Minister Arsen Avakov gave the death toll on his Facebook page Tuesday, adding that 20 government troops were also injured during fighting in Slovyansk, a city of 125,000. It was not exactly clear when the deaths took place. Gunbattles around the city Monday were the interim government's most ambitious effort to date to quell weeks of unrest in Ukraine's mainly Russian-speaking east.
Avakov said Monday about 800 pro-Russia forces in and around Slovyansk were deploying large-calibre weapons and mortars and there were injured on both sides.
By Tuesday morning, Ukrainian forces had taken hold of a key checkpoint north of the city, dealing a blow to insurgent lines of communication. The checkpoint had come under repeated attack since the government offensive began.
In Donetsk, a major city 120 kilometres south of Slovyansk, international flights were suspended Tuesday. The Donetsk airport said the cancellations followed a government order.
Ukraine is facing its worst crisis in decades as the polarized nation of 46 million tries to decide whether to look toward Europe, as its western regions want to do, or improve ties with Russia, which is favoured by the country's many Russian-speakers in the east. Dozens of government offices and police stations in eastern Ukraine have been seized by armed insurgents and anti-government crowds over the past several weeks.
The central government attempted to re-establish control Tuesday over the predominantly Russian-speaking region of Odessa, where 46 people died Friday after a pro-Ukraine march led to shootings and fighting between the two sides. In the melee, a building fire broke out, killing many.
In a statement published on the president's website, the Kyiv authorities announced they were firing the acting governor and replacing him with member of parliament Ihor Palytsya. On Saturday, Odessa's police chief was fired.
The concern that Odessa could be the next region to fall to pro-Russian forces -- particularly after 67 people detained in Friday's rioting were released by the police under pressure from an angry crowd -- has sparked concern in Kyiv. The government sent an elite national guard force to Odessa, where it could be seen Monday patrolling the streets.
The goals of the pro-Russian insurgency are ostensibly broader powers of autonomy for the region, but some insurgents do favour separatism or even joining Russia.
Leaders of the anti-government movement say they plan to hold a referendum on autonomy for eastern regions on May 11, although no visible preparations for the vote have yet been seen.
The Russian Foreign Ministry has put the blame for the unrest squarely on the interim government in Kyiv, which it says "stubbornly continues to wage war against the people of its own country." The ministry has urged what it called the "Kyiv organizers of the terror" to pull back their troops from the east and hold peaceful negotiations to resolve the crisis.
Ukraine authorities blame Moscow for fomenting the unrest in the east, saying it's an attempt to derail Ukraine's May 25 presidential election. Ukraine's former president fled to Russia in February after months of protests against his government.