The attack on the OGA, as indicated in this video, started at 7 minutes and 30 seconds.
http://www.youtube.com/watch?v=4Az_5F9n14Q
The number of people storming the building grew and grew.
Euromaidan supporters blocked the doors of the Regional State Administration from inside. Then the attackers broke windows on the first floor and entered the OSA through them.
At the same time, some of those who stormed the Oblast State Administration try to enter the building through Mironositskii Street. They also broke windows in the building.
Shots were heard from the windows of the OSA on the second floor.
A MediaPort correspondent tells of wounded on both sides – people received skull fractures.
UDATE 14:30 – News has been received that the exits of the University and Gosprom metro stations are closed; trains are not stopping at them. City minibuses are not going to downtown Kharkov. As MediaPort has observed, the police at this point have not interfered in the conflict. Those attacking with St. George ribbons on have seized several “Euromaidaners.”
UPDATE 14:50 – Those storming the OGA have put up a Russian flag from one of the windows. Russian Federation flags have also appeared at the main entrance and on the roof of the Regional State Administration.

MediaPort reports that the bleeding Euromaidan activist and writer Serhiy Zhadan was dragged to the stage and kicked.
The oblast Interior Minstry administation was not able to answer if there are any people detained, how many suffered, and why the police did not react when people with rocks were seizing the OSA building. Meanwhile, MediaPort had observed how the police was leading out Eurmaidan supporters.
There were buses with Russian license plates too.

UPD 16.55 The local Interior Ministry's administration informs that 68 people suffered from the OSA storming by the participants of "patriotic Kharkovians" demonstration. Criminal proceedings have been opened under part 1 of Article 294 of the Criminal Code (mass riots).
UPD 17.06 The Russian flags that were hung on the roof and from the windows were taken down.
UPD 17.25
Interior Minister Arsen Avakov: "Any information that any kind of squads are moving our of Kyiv into Kharkiv does not correcpond to reality. The situation in Kharkiv will be normalised by joint activities of people of good sense with the help of law-enforcing organs and does not require any forceful actions. At present, the Kharkiv OSA is freed from outsiders, invistigations are being carried out to fixate the damage done. At the same time, police have taken around 30 people out of the zone of conflict. They are heading to three police stations to record the traumas received and for making protocols. I would like to note that the synchronous nature of similar events at the same time in several Oblast centeres of Ukraine on the background of an activisation of the Russian military presence in Crimea can indicate to a common plan."Original link: http://www.mediaport.ua/shturm-obladministracii-v-harkove Tranlslated by William Risch and Alya Shandra