Hundreds of pro-Russian separatists in eastern Ukraine seized another regional government headquarters on Tuesday.<br/> <br />This one, in Luhansk, where they were unopposed by police.<br/> <br />The central government has all but lost control of its police forces in parts of eastern Ukraine.<br/> <br />That's were an armed rebel movement seeks more autonomy or outright annexation into neighboring Russia.<br/> <br />Evicting the separatists has been a struggle for authorities.<br/> <br />On Tuesday, Ukrainian Prime Minister Arseny Yatseniuk urged parliament to adopt a new constitution to prevent further unrest.<br/> <br />(SOUNDBITE) (Ukrainian) ARSENY YATSENIUK, PRIME MINISTER OF UKRAINE, SAYING:<br/> <br />"The Ukrainian Constitution must become a document of national unity; the unity that is highly needed in this country; the unity which is the only guarantee for preserving the Ukrainian state…and will preserve it as an integral, independent, European state where every Ukrainian has his legal place."<br/> <br />Tuesday mo
