Pro-Russian separatists in Ukraine opened fire with automatic weapons and threw stun grenades at the local police headquarters in the eastern city of Luhansk on Tuesday, a Reuters photographer said.
Around 20 gunmen shot at the building, trying to force police to surrender their weapons.
Meanwhile, Pro-Russian separatists took control of the regional prosecutor's office and television center in the eastern city of Luhansk, having earlier seized the government headquarters, a Reuters photographer said.
The photographer saw separatists inside the prosecutor's office and gunmen guarding the entrance of the television center. The gunmen said they were in control of the building and Interfax news agency said protesters had burned the Ukrainian flag.
This comes after hundreds of pro-Russian separatists seized the regional government headquarters in Luhansk, unopposed by police, underlining the lack of control of central government over swathes of eastern Ukraine.
Lines of riot police surrounded the back of the building, facing hundreds of men and women. At the front, dozens of men, some in green camouflage and holding shields, walked into the imposing, white building, while others smashed windows and raised the Russian tricolour.
The government in Kiev has all but lost control of its police forces in parts of eastern Ukraine since pro-Russian activists seized buildings in the region's second biggest city of Donetsk and several smaller towns.
In separatist-held Slaviansk, the self-declared mayor said he would discuss the release of detained military observers only if the European Union dropped sanctions against rebel leaders.
"The regional leadership does not control its police force," said Stanislav Rechynsky, an aide to Interior Minister Arsen Avakov, referring to events in Luhansk where separatists had earlier only occupied the local security services' building.
"The local police did nothing."
He added that the ministry had information that they would next try to take the local television centre.
Some protesters, who say they are not properly represented in Kiev by Ukraine's new pro-Western rulers, called on the police to handover their arms.
Local reactions:
Ukraine's acting president demanded the dismissal on Tuesday of police chiefs in the eastern cities of Donetsk and Luhansk, saying much of the police in the east of the country had proven incapable of fulfilling their duties.
The statement by Oleksander Turchynov followed the takeover by armed pro-Russian separatists of several state buildings in Luhansk on Tuesday, unopposed by police.
"The overwhelming majority of law enforcement bodies in the east are incapable of fulfilling their duty to defend our citizens," he said.
International reactions:
U.S. Treasury Secretary Jack Lew said on Tuesday that international sanctions on
Russia over its policies toward Ukraine were putting pressure on Russia's economy, and more actions may be taken if Russia's stance does not change.
"You have to look over the period of time Russia went into Crimea, since we've imposed sanctions, there has been a quite substantial deterioration in Russia's already weak economy. We see it in their stock exchange, we see it in their exchange rate, we see it in a number of important economic indicators," Lew told a U.S. House Appropriations subcommittee hearing.
Asked whether the United States and European allies will target Russia's energy or banking sectors with sanctions, said those actions have been considered and could be taken under a presidential executive order that provides sanctions authority.
"We need to continue to keep our options open. We are prepared to take more action and we've made clear that we're prepared to take more action if the policy of Russia doesn't change," Lew said.
REUTERS