Crimea crisis and unrest in eastern Ukrainian cities
Pro-Russian protesters gather outside the regional administrative building in the eastern city of KharkovReuters

Pro-Russian protesters who stormed state buildings in the eastern Ukrainian city of Donetsk have declared independence from Ukraine even as the Kiev administration scrambles government officials across the restive region.

After declaring independence, the protesters from the "People's Republic of Donetsk" have requested President Vladimir Putin to send Russian troops to maintain stability.

The anti-Kiev demonstrators have removed the Ukrainian flag and are hoisting the Russian flag.

In a dramatic turn of events after Crimea's breakaway from Ukraine, the eastern Ukrainian cities of Donetsk, Lugansk and Kharkov have been witnessing rallies and unrest over the weekend demanding a Crimea-style referendum.

The protesters have also announced the city will hold a referendum to decide on secession from Ukraine on 11 May.

The ongoing unrest bears a striking resemblance to the earlier series of events when pro-Russian forces seized government buildings in Crimea and eventually claimed entire control of the peninsula. This was followed by a hastily arranged referendum. Other cities are now undergoing similar turmoil.

Meanwhile, Ukraine has blamed Russia for the unfolding events and beefed up security along its borders.

Ukraine's interim prime minister expressed concern that Russian troops are ready in Ukraine's border regions to invade.

"There is no evidence that the Russian Federation withdrew its troops from the border, there is nothing, but a manifestation of the signs that they want to show as if they have withdrawn their troops. Merely, the troops are in the 30-kilometer zone from the Ukrainian borders. Therefore, virtually no one withdrew the troops," said Arseniy Yatseniuk.

"The citizens of Donetsk, Lugansk and Kharkov want to live in a single, unitary country. To do this, we began the process of constitutional changes to transfer powers to the places that everyone felt worthy citizen of the country, which affects the power in Ukraine and in the field. Any other calls for federalisation are attempts at destruction of Ukrainian statehood."

Interior minister Arsen Avakov has been sent to Kharkov while first deputy prime minister Vitaliy Yarema has left for Donetsk to deal with latest bout of unrest.