Kozak

"Going out onto the streets and protesting in a traditional manner is associated with risk, so for the moment we are focused on organising our actions online, in a safe manner," said Kozak. "For now, this is a warning strike, but we might escalate it if our request to dismiss the education minister is not heard."

The sons of two Russian politicians sanctioned by the EU over the Ukraine crisis are carrying out their business activity in Bulgaria, according to the daily Trud.

Alexey Kozak, whose father is Russian Deputy Prime Minister Dmitry Kozak, and Russian Parliament Legal Committee Chairman Vladimir Pligin's son Aleksander both own enterprises based in the Black Sea city of Varna.

The European Union put Russian Deputy Premier Dmitry Kozak on an expanded sanctions list, joining the US in protesting Russia's actions in Ukraine.

Crimea, which joined Russia last week, could become a special economic zone, Russia's Prime Minister said.

With his comments, Dmitry Medvedev confirmed earlier reports by Russian newspaper Vedomosti, which suggested the peninsula would be managed through a separate economic program and even by a "special corporation".