VLADIMIR PUTIN

In what is being called an "act of aggression," pro-Russian activists seized government buildings and a police station, witnesses said.

President Putin also said Russia has no plans to halt deliveries to Ukraine, but it might make Kiev pay up front.

The U.S. said it's taking steps to assist Ukraine, including the provision of emergency finance and technical assistance in energy security.

Russia energy giant Gazprom says Ukraine owes $2.2 billion for gas supplies and missed the deadline for paying for its March supplies.

The capital flight coincides with slumping investment and a sharp deterioration in business confidence.

Officials on both sides of the Ukraine crisis are pointing to each other for escalating tensions in Eastern Ukraine.

Buildings were also seized in Kharkiv and Donetsk, where pro-Russia demonstrators called for a “people’s city council.”

Ukrainian officials have accused Russia of sending FSB operatives, and explosives, into the country to stamp out anti-government protests.

Move aims to ease tension after Moscow accused the bank of illegally blocking the transaction.

NATO cites key signs at the border indicating that Russia may be ready to pounce.

Russia's continued troop movements on Ukraine border worry NATO commander

A Russian news organization reported that Ukraine had asked to resume normal relations with Russia once again.

In a statement, the Russian Foreign Ministry suggested the action would have consequences for the U.S. embassy and consulate in Russia.

The E.U.'s effort is expected to be supplemented by both U.S. and IMF aid packages.

Russian PM Medvedev flaunted Russia's annexation of Crimea on Monday by flying there and announcing a special economic zone for the region.

Kerry tells Moscow that progress depends on a Russian troop pullback from Ukraine's borders.

Obama expresses continued concern over Russian troop buildup along the Crimean border.

Putin's Crimea annexation has sparked a new EU urgency to find energy supplies outside of Russia, but weaning will be slow and difficult.

"We know that Russian military doctrine advocates escalating in order to de-escalate," British Defense Secretary Philip Hammond said, adding, "this escalation we're seeing is indeed simply the playing out of the classic Russian military doctrine."

Turchinov's request, if approved, would bring troops from the U.S. and EU into close proximity with Russian forces.

Obama said he was concerned at the possibility of further Russian "encroachment" into Ukraine and believed Putin was still "making a series of calculations."