1. A nurse holds a weapon as she helps a wounded pro-Russian gunman to exit a car in front of a hospital in Slovyansk, eastern Ukraine, on May 5, 2014. Ukrainian troops fought pitched gun battles Monday with a pro-Russia militia occupying the eastern city -- an apparent escalation of their efforts to bring the region back under government control.
2. A crowd of some 300 pro-Russian separatists clash with riot police as they storm the prosecutor's office in the eastern Ukrainian city of Donetsk on May 1, 2014. The mob hurled rocks and Molotov cocktails at around 100 riot police defending the building, who responded with stun grenades and tear gas.
3. A pro-Russian activist breaks a window in the offices of Industrial Union of Donbass Corporation in Donetsk, eastern Ukraine, on May 3, 2014, which was captured to honor the memory of fallen comrades during fighting with pro-Ukrainian activists in Odessa on Friday. The building houses the offices of Industrial Union of Donbass Corporation, owned by government-appointed Donetsk region governor and billionaire Serhiy Taruta. No police were deployed to block the building takeover.
4. Pro-government supporters march during a protest on April 28, 2014 in Donetsk, Ukraine. Several people were injured when pro-Russian activists attacked the march.
5. Pro-Russian activists march on May 1, 2014 in Donetsk, Ukraine. Following the rally, activists marched through the city and clashed with police during a takeover of the city prosecutors office. The activists confiscated riot gear from the defeated police force guarding the building.
6. A pro-Russian activist aims a pistol at supporters of the Kiev government during clashes in the streets of Odessa May 2, 2014. Police said a man was shot dead in clashes between a crowd backing Kiev and pro-Russian activists in the largely Russian-speaking southern port of Odessa, which lies west of Crimea, annexed by Moscow in March.
7. Pro-Russian separatists block the Kramatorsk-to-Slovyansk road on May 2, 2014. Russia warned on May 2 that Ukraine's use of the army against its own people in the east will lead to catastrophe and urged the West to renounce its "destructive policies."
8. Ukrainian soldiers arrive to reinforce a checkpoint which troops seized in the early morning in the village of Andreevka, 7 km from the center of the southern Ukrainian city of Slovyansk, on May 2, 2014. Ukraine's military lost two helicopters and two servicemen on May 2 in a deadly offensive launched just before dawn against pro-Russian rebels holding the flashpoint town of Slovyansk, insurgents and authorities said.
9. Armed pro-Russian activists take positions in Luhansk, eastern Ukraine, on May 3, 2014. The shooting with automatic weapons started between pro-Russian activists and presumably Ukrainian police near the building of the regional military commissariat.
10. A tarp covers the body of a pro-Russian activist after he was killed during an attack on roadblock by Ukrainian soldier on May 3, 2014 in Andreevka, Ukraine. According to the activists, soldiers opened fire on the roadblock and killed three activists and wounded another 15. Over the past couple of days the Ukrainian army has been assaulting pro-Russian checkpoints in and around Andreevka and Kramatovsk which sit on the edge of Slovyansk, a pro-Russian activist stronghold.
11. Ukrainian Army soldiers line up in front of pro-Russia civilians who were blocking the road to Andreevka on May 2, 2014. Russia has massed tens of thousands of troops in areas near Ukraine's border. Kiev officials claim Russia is preparing to invade and that it is fomenting the unrest in the east, where insurgents have seized government buildings in about a dozen cities in towns. Moscow denies the allegations, but Foreign Minister Sergey Lavrov has warned Russia would respond to attacks on Russian citizens or interests in the east.
12. A man tries to climb a flag pole to place a Ukrainian flag outside the burnt trade union building in Odessa, Ukraine, on May 4, 2014, where people died in in a fire that tore through the building.
13. A Pro-Russian activist pulls the hair of a woman, pro-Ukrainian supporter, during an argument outside the burned trade union building in southern Ukrainian city of Odessa on May 3, 2014.
14. Pro-Russian protesters attack a pro-Ukranian protester during a pro-Ukraine rally in Donetsk on April 28, 2014. Several people were wounded when what appeared to be stun grenades exploded during a rally in support of Ukrainian unity in the eastern, separatist-held city of Donetsk on Monday, a Reuters reporter said.
15. A group of pro-Russia militia members armed with assault rifles walk in a street in Kramatorsk, Ukraine, on May 3, 2014. On Saturday, news reports claimed fighting broke out in the city of Kramatorsk, about 15 km (10 mi) south of Slovyansk.
16. Local citizens collect parts of a downed Ukrainian military helicopter near a small town Raigorodok, outside Slovyansk on May 6, 2014. The helicopter was forced to make an emergency landing Monday during intense fighting in Slovyansk and was later destroyed by Ukrainian troops, who sought to ensure it did not fall into the hands of insurgent forces.
17. A group of Ukrainian police officers stand outside the administration building which had been captured by Pro-Russian activists in the center of Luhansk, one of the largest cities in Ukraine's troubled east, on April 29, 2014. The Ukrainian police capitulated their position without a fight.
18. Pro-Russian activists storm the prosecutors office on May 1, 2014 in Donetsk, Ukraine. Activists marched to the prosecutors office and overran the police guarding the building. After taking control of the building and confiscated the police riot gear, police officers were set free.
19. Police officers flee during clashes with Pro-Russian activists in front of the regional administration building in Donetsk on May 1, 2014. The clash came after a march by several hundred people carrying flags of the Donetsk People's Republic, a movement that seeks either greater autonomy from the central government, or independence and possible annexation by Russia.
20. Masked pro-Russian demonstrators break into storerooms inside the military Prosecutor's Office in Donetsk on May 4, 2014.
21. A Pro-Russian activist throws a Ukrainian flag out of a window of the military Prosecutor's Office in Donetsk on May 4, 2014.
22. Pro-Russian supporters shout slogans during a rally after a funeral ceremony of Vyacheslav Markin, a regional parliament deputy who died in a fire at the trade union building in Odessa on May 5, 2014.
23. A pro-Russian activist tent camp burns in front of the trade union building in Odessa May 2, 2014. More than 40 people were killed in a fire on Friday in the trade union building in the center of Ukraine's southern port city of Odessa, regional police said.
24. A protester throws a petrol bomb at the trade union building in Odessa on May 2, 2014.
25. People wait to be rescued on upper stories at the trade union building in Odessa on May 2, 2014.
26. People walk inside the burnt trade union building, in Odessa, Ukraine, on May 4, 2014, where people died in in a fire that tore through the building. More than 40 people died in riots two days earlier, some from gunshot wounds, but most in a horrific fire that tore through a trade union building.
27. Members and supporters of Ukrainian far-right radical groups take part in a torch-light procession to commemorate people killed in recent clashes during protest rallies held by Euromaidan movement in central Kiev on April 29, 2014.
28. Ukrainian soldiers stand at a checkpoint near the eastern Ukranian city of Slovyansk on May 5, 2014. Four Ukrainian troops were killed and 30 wounded in intense fighting around the rebel-held town of Slovyansk on May 5, the interior ministry said. The ministry added that the pro-Russian gunmen controlling the town were using civilians as human shields and were shooting from houses, some of which were on fire.
29. Four pro-Russian militants lay on the ground with hands tied after being arrested on suspicion of the implementation of MANPADS (Man-portable air-defense systems) shots fired at a Ukrainian military helicopter on May 2, 2014. Authorities say pro-Russian insurgents used shoulder-launched rockets to bring down two Mi-24 helicopters.
30. Members of Ukraine's State Security Administration (right) clash with members of the Euromaidan movement's self-defense units during a rally outside the cabinet of ministers building in Kiev on April 30, 2014.
31. Police officers take cover under their shields as pro-Russian activists storm the prosecutors office on May 1, 2014 in Donetsk.
32. A relative touches the body of 17-year-old Vadim Papura during a religious service outside his apartment block in Odessa on May 6, 2014. Papura died after jumping out of the burning trade union building in an attempt to escape Friday's fire that killed most of the 40 people that died after riots erupted last Friday.
33. Pro-Russian protesters burn a Ukrainian flag outside the district council building in Donetsk on May 4, 2014. Ukrainian Prime Minister Arseny Yatseniuk accused Russia on Sunday of engineering clashes in Odessa that led to the deaths of more than 40 pro-Russian activists in a blazing building and pushed the country closer to civil war.
34. Pro-Russian protesters attack the gates of a police station building in Odessa, on May 4, 2014. Several prisoners that were detained during clashes that erupted Friday between pro-Russians and government supporters were released under the pressure of protesters that broke into a local police station and received a hero's welcome by crowds.
35. Masked pro-Russiam men hold a wounded comrade during the assault of the prosecutor's building, after a pro-Russia demonstration in Donestsk on May 1, 2014.
36. An armed pro-Russian man stands at a checkpoint in the town of Slovyansk on May 6, 2014.
37. A pro-Russian separatist, photographed after some 300 of his fellow activists seized control of the prosecutor's office in Donetsk on May 1, 2014.
38. A Ukrainian paratrooper walks next to an APC as he and other comrades block a road outside the town of Slovyansk on May 4, 2014. Ukrainian authorities are currently seeking to form a security cordon around the town. They have repeatedly claimed victories in capturing checkpoints surrounding the city, although such boasts have often proven overstated.
39. Pro-Russian militants escort a man with his eyes covered outside the regional state building they seized in Donetsk on May 5, 2014.
40. A man shouts as he gestures in front of police guarding the burned trade union building in Odessa, Ukraine, on May 3, 2014, where more than 40 people died trying to escape during clashes the day before.