Ukrainian authorities release video of what appears to show shots being fired at a Ukrainian border patrol plane.<br /> <br />Border guards say the plane came under fire on Sunday while flying near the administrative border with Russian-occupied Crimea.<br /> <br />A spokesman says three crew members were on an observation mission and that no one was hurt.<br /> <br />Russian forces tightened their grip on Crimea Sunday.<br /> <br />The conflict has been bloodless so far, but tensions are mounting.<br /> <br />Breakaway pro-Russian leaders in Crimea's parliament have decided to make the region a part of Russia.<br /> <br />Ukrainian Prime Minister Arseny Yatseniuk says he's fighting for the country's unity:<br /> <br />(SOUNDBITE) (Ukrainian) UKRAINIAN PRIME MINISTER, ARSENY YATSENIUK, SAYING:<br /> <br />"This is our land, our parents and grandparents spilled their blood for this land. We will not give up a single centimeter of Ukrainian land. Let Russia and the Russian president know this."<br /> <br />Rival rallies continue throughout
