A column of armored vehicles flying Russian flags drove into a Ukrainian city controlled by pro-Russian insurgents Wednesday, dampening the central government's hopes of re-establishing control over restive eastern Ukraine.
Still, it was far from clear just who these mostly masked men were and what their presence meant for eastern Ukraine, which has seen a surge of support for closer ties with Russia and against the new government in Kiev, which wants closer links to Europe.
Troops in camouflage sat atop the six vehicles as they entered the city of Slovyansk, a hotbed of unrest against Ukraine's interim government.
Insurgents in Slovyansk last weekend seized the police headquarters and the administration building, demanding broader autonomy for eastern Ukraine and closer ties with Russia. Their actions have been repeated in at least eight other cities in eastern Ukraine.
One of the men on the vehicles in Slovyansk said they were Ukrainian soldiers who had defected to the pro-Russian side - which raises the specter of an uprising led by disgruntled Ukrainian forces.
But an AP journalist overheard another soldier suggesting that they were forced to hand over the vehicles.
''How was I supposed to behave if I had guns pointed at me?'' the soldier, who did not identify himself, asked a resident.
Breaking hours of silence, the Ukrainian Defense Ministry issued a statement saying Ukrainian troops had entered Kramatorsk, south of Slovyansk, on Wednesday morning. There residents and ''members of Russian sabotage groups'' seized six armored personnel vehicles and drove them to Slovyansk.
The military insisted the armed men seen on APCs in Slovyansk were not Ukrainian forces but added ''the whereabouts of the Ukrainian servicemen'' had yet to be established.
Eastern Ukraine was the support base for ousted President Viktor Yanukovych, who fled to Russia after months of protests over his decision to back away from closer relations with the European Union and turn toward Russia. Opponents of the government that replaced him fear the new authorities will repress eastern Ukraine's large Russian-speaking population.
Reflecting the West's concern, German Chancellor Angela Merkel called Russian President Vladimir Putin late Tuesday to discuss the situation in Ukraine and preparations for diplomatic talks in Geneva on Thursday.
The Kremlin said Putin told Merkel that ''the sharp escalation of the conflict places the country in effect on the verge of a civil war.'' Merkel's office said she and Putin had ''different assessments'' of the events