Ukraine put its police on high alert after dozens of armed pro-Russia men stormed and seized local government buildings in Ukraine's Crimea region early Thursday and raised a Russian flag over a barricade.
The renewed tension in this strategic peninsula that houses Russia's Black Sea fleet came as lawmakers in Kiev were expected to approve the new government, but also a day after clashes between pro- and anti-Russian demonstrators in Crimea's regional capital, Simferopol.
Russia has questioned the legitimacy of the new Ukrainian authorities after pro-Russian President Viktor Yanukovych fled last week, and it has accused them of failing to control radicals who threaten the Russia-speaking population in Ukraine's east and south, which includes the Crimean Peninsula.
The men occupying the local parliament building did not immediately voice any demands but threw a flash grenade in response to a journalist's questions. They wore black and orange ribbons, a Russian symbol of the victory in World War II, and put up a sign saying "Crimea is Russia."
The events unfolding in Crimea highlighted the divided allegiances between Russia and the West Ukraine after Yanukovych fled the capital, Kiev.
Ukraine's acting interior minister Arsen Avakov said on his Facebook page on Thursday that areas around the occupied buildings were being sealed off by police.
"Measures have been taken to counter extremist actions and not allow the situation to escalate into an armed confrontation in the center of the city," he said.
Phone calls to the Crimean legislature rang unanswered, and its website was down. Refat Chubarov, a local leader of the Tatar community that support the new authorities in Kiev, wrote on his Facebook page early Thursday that the two buildings were taken overnight by uniformed men.
Russian President Vladimir Putin put the military on alert for massive exercises involving most of the military units in western Russia, and the military announced measures to tighten security at the headquarters of Russia's Black Sea Fleet on the peninsula.
The maneuvers will involve some 150,000 troops, 880 tanks, 90 aircraft and 80 navy ships, and are intended to "check the troops' readiness for action in crisis situations that threaten the nation's military security," Defense Minister Sergei Shoigu said in remarks carried by Russian news agencies.
The move prompted a sharp rebuke from U.S. Secretary of State John Kerry, who warned Russia against any military intervention in Ukraine.
Russia denied the military maneuvers were connected to the situation in Ukraine, but the massive show of force appeared intended to show both the new Ukrainian authorities and the West that the Kremlin was ready to use all means to protect its interests.