Several thousand pro-Russian demonstrators in the eastern Ukrainian city of Luhansk have seized the regional administration building, the prosecutor's office, the main police station, and the local television center.
The regional administration building was the first to fall to protesters on April 29 and afterward a group of several hundred people went to the prosecutor's building and seized it also.
Pro-Russian demonstrators then took over the local television center and the police station.
There were reports of gunfire at the police station.
Acting Ukrainian President Oleksander Turchynov demanded the dismissal of the Luhansk and Donetsk police commanders.
Turchynov said in a statement that the local police commanders in those two cities had "shown inaction, powerlessness, and in some cases criminal treachery."
There were reports the regional police chief in Luhansk has resigned, yielding to the demands of protesters outside the police station.
The security situation in eastern Ukraine where insurgents have seized government buildings in at least 10 towns and cities has been deteriorating.
The mayor of the eastern Ukrainian city of Kharkiv Hennadiy Kernes was shot in the back on April 28.
Kernes was flown to Israel on April 29 and has successfully undergone surgery although Israeli doctors say Kernes may have to undergo a second surgery.
Meanwhile, the head of the OSCE was in Kyiv on April 29 to discuss efforts to secure the release of a group of OSCE monitors held by pro-Russian militants.
WATCH: Protesters Take Over Luhansk Regional Building
Lamberto Zannier, the secretary-general of the Organization for Security and Cooperation in Europe, met with Ukraine's acting Foreign Minister Andriy Deshchytsya and with U.S. Ambassador Geoffrey Pyatt.
Zannier declined to give an update on the fate of the seven European monitors who are held in Ukraine's rebel-controlled eastern city of Slovyansk.
The self-declared separatist mayor of Slovyansk said later on April 29 that there had been "good progress" in talks with OSCE officials to secure the monitors' release.
Vyacheslav Ponomaryov declined to give a time frame of when the observers could be released.
The OSCE officials left without comment.
Based on reporting by Reuters, AFP, and Interfax