In what is becoming a semi-regular event in Ukraine, protestors stormed government buildings. This time it was by pro-Russian demonstrators in a seemingly coordinated attack on three eastern Ukrainian cities: Donetsk, Luhansk, and Kharkiv.

(AP)

In Donetsk, the BBC explains, a group of about 50 people broke away from the main protest and managed to get past riot police and into the building, where they smashed windows, gave speeches, and put up a banner that said "Donetsk Republic." Car tires have been brought in (see right) to barricade the building from Ukrainian forces trying to retake it. Donetsk has become the site for many pro-Russian rallies in the days surrounding Russia's annexation of Crimea, some of which have turned deadly

According to Reuters, about 100 people are currently in the building, which houses the offices of regional governor and billionaire Serhiy Taruta.

In Luhanska, protestors scaled a security services building to put a Russian flag on the roof. They also threw eggs, rocks, a smoke grenade and then a firebomb at the building ("The flames were reportedly quickly extinguished," said the AP). Fifteen people were arrested in Luhansk yesterday, accused to trying to mount an armed takeover of the region. Hundreds of machine guns, a grenade launcher, grenades, five handguns and petrol bombs were seized.

There aren't details on what happened in Kharkiv yet except that it was similar to demonstrations outside the other two cities.

Ukraine's interim president will hold an emergency meeting with security officials to deal with the matter. Interior minister Arsen Avakov said police would restore order to the regions "without bloodshed."

Avakov blamed Russian president Vladimir Putin and ousted Ukrainian president Viktor Yanukovich of ordering and financing the protests, calling demonstrators "paid provocateurs" in a statement on his Facebook page.