Ukrainian security forces patrol in the village of Bobrovyshche on July 14, 2015. More than 6,400 people have been killed in the conflict in Ukraine since April 2014, the United Nations says. ALEXANDER ZOBIN/AFP/Getty
Ukrainian security forces on the lookout in Bobrovyshche on July 14. The country's troops face daily attacks from Russian-backed separatists despite a ceasefire being in place. SERGEY BOBOK/AFP/Getty
A man with a machine gun is among the Ukrainian troops standing guard in Krimskoe town of Luhansk, Ukraine, on June 25. Viktor Koshkin/Anadolu Agency/Getty Images
Shelling between Ukrainian troops and pro-Russian rebels leaves damage in Donetsk, Ukraine, on Monday, June 1. Mstyslav Chernov/AP
A Ukrainian serviceman fires a grenade launcher on the front lines near Donetsk on Saturday, May 30. GENYA SAVILOVGENYA SAVILOV/AFP/Getty Images
An American soldier, right, trains Ukrainian troops on Tuesday, April 21, near Yavoriv, Ukraine. Operation Fearless Guardian, a six-month training exercise, involves about 300 members of the American 173rd Airborne and about 900 Ukrainian National Guard troops. Pete Kiehart/Getty Images
Residents flee with salvaged belongings during renewed fighting in the Jabunki neighborhood near the airport in Donetsk on Monday, April 13. ODD ANDERSEN/AFP/Getty Images
A mortar round sticks out of the ground near a destroyed tank at a former Ukrainian army checkpoint outside Chornukhyne, Ukraine, on Monday, March 2. Russian-backed separatists had recently overran the area. Vadim Ghirda/AP
An instructor of the Ukrainian volunteer Azov Battalion conducts training exercises in Kiev, Ukraine, on Sunday, March 1. YURY KIRNICHNY/AFP/Getty Images
A woman makes her way across a bridge destroyed in heavy fighting in Donetsk, Ukraine, on March 1. Vadim Ghirda/AP
A volunteer gives humanitarian aid to residents of Popasna, Ukraine, on Saturday, February 28. Evgeniy Maloletka/AP
A Ukrainian serviceman climbs out of a tank at a checkpoint near Horlivka, Ukraine, on Monday, February 23. Anatolii Stepanova/AFP/Getty Images
A member of a Ukrainian military medical unit cries during a ceremony in Artemivsk, Ukraine, on February 23. Four of his comrades were killed near Debaltseve, Ukraine. Evgeniy Maloletka/AP
A man holds a Ukrainian flag as he covers a victim of an explosion in Kharkiv, Ukraine, on Sunday, February 22. The explosion during a peaceful protest left two dead and 15 wounded. Andriy Marienko/AP
Pro-Russian rebels stationed in Horlivka launch missiles on Wednesday, February 18. ANDREY BORODULIN/AFP/Getty Images
Pro-Russian separatists take position near Uglegorsk, Ukraine, on February 18. VASILY MAXIMOV/AFP/Getty Images
An army ambulance damaged in recent shelling lies by a road near Svitlodarsk, Ukraine, on Sunday, February 15. Petr David Josek/AP
Ukrainian servicemen play with a soccer ball on a road between Svitlodarsk and Debaltseve on February 15. VOLODYMYR SHUVAYEV/AFP/Getty Images
A woman salvages items February 15 from the rubble of a destroyed clinic where she had worked in Opytne, Ukraine. PETRO ZADOROZHNYY/AFP/Getty Images
People carry a refrigerator through a balcony at an apartment building that was damaged in recent shelling in Svitlodarsk on February 15. Petr David Josek/AP
A recent ceasefire was brokered during marathon talks in Minsk, Belarus. From left, Belarusian President Alexander Lukashenko, Russian President Vladimir Putin, German Chancellor Angela Merkel, French President François Hollande and Ukrainian President Petro Poroshenko gather before negotiations begin on Wednesday, February 11. Mykola Lazarenko/Pool/AP
People stand beside the body of a woman killed during shelling in Kramatorsk, Ukraine, on Tuesday, February 10. VOLODYMYR SHUVAYEV/AFP/Getty Images
A volunteer gets a medical checkup at a military base for pro-Russian rebels February 10 in Donetsk, Ukraine. Pierre Crom/Getty Images
Ukrainian volunteer fighters and policemen arrest two men in Kiev, Ukraine, on February 9. The men allegedly arrived from Donetsk and were suspected of participating in pro-Russian rebel activities and organizing terrorist attacks in the Ukrainian capital. SERGEI SUPINSKY/AFP/Getty Images
Residents unload humanitarian aid in Debaltseve on Friday, February 6. Petr David Josek/AP
A man rides a bicycle in Vuhlehirsk, Ukraine, on February 6. Petr David Josek/AP
A child waits on a bus to leave Debaltseve on Tuesday, February 3, after increased fighting in the region. Petr David Josek/AP
A man stands next to his car in Donetsk on Sunday, February 1, after it was destroyed by shelling. DOMINIQUE FAGET/AFP/Getty Images
The body of a civilian killed during shelling lies on the ground in Donetsk on Friday, January 30. Vadim Braydov/AP
People in Mariupol, Ukraine, pour soil into the grave of a recent shelling victim on Monday, January 26. Evgeniy Maloletka/AP
Ukrainian servicemen prepare ammunition at a position on the front line near Mariupol on January 26. ANATOLII BOIKO/AFP/Getty Images
A man injured during shelling in Mariupol sits in an emergency hospital on January 26. Oleksandr Stashevskiy/AFP/Getty Images
A piece of an exploded missile sits lodged in the ground outside an apartment building in the Vostochniy district of Mariupol on Sunday, January 25. Evgeniy Maloletka/AP
A resident walks by a burning building in Mariupol on Saturday, January 24. Sergey Vaganov/AP
A pro-Russian rebel takes cover from shelling in the Kievsky district of Donetsk on Thursday, January 22. Manu Brabo/AP
People in downtown Donetsk react as Ukrainian prisoners of war are handed over by pro-Russian rebels on January 22. ALEXANDER ERMOCHENKO/EPA/LANDOV
A trolleybus is damaged in Donetsk's Lenin District after its station was hit by a shell on January 22. Nikolai Muravyev/ITAR-TASS/Landov
A rebel takes aim while protecting a supply position in the Kievsky district of Donetsk on January 22. Manu Brabo/AP
Rubble and debris cover the airport in Donetsk on Wednesday, January 21. Igor Ivanov/AP
Vladimir Bovrichev cries next to the body of his 4-year-old son, Artiam, during Artiam's funeral on the outskirts of Donetsk on Tuesday, January 20. The boy was killed during a Ukrainian artillery strike. Manu Brabo/AP
Women sit in a shelter during a battle in Donetsk on Sunday, January 18. Manu Brabo/AP
A building hit by Ukrainian artillery is seen in the Voroshilovsky area of Donetsk on January 18. Manu Brabo/AP
Men from the Azov Volunteer Battalion board a bus in Kiev to join the fight against the rebels on Saturday, January 17. Sergei Chuzavkov/AP
Rebels sit atop a tank at a checkpoint north of Luhansk, Ukraine, on Wednesday, January 14. Mstyslav Chernov/AP
A Ukrainian soldier looks down from a military truck at the Donetsk airport on Tuesday, January 6. The airport has been the scene of some of the fiercest fighting in eastern Ukraine. Mstyslav Chernov/AP
Ukrainian President Petro Poroshenko gives a speech as he hands over new military equipment to forces near the city of Ghytomyr, Ukraine, on Monday, January 5. SERGEI SUPINSKY/AFP/Getty Images
A Ukrainian volunteer fighter fires a machine gun at pro-Russian rebels near the village of Pisky, Ukraine, on Saturday, January 3. VASILY MAXIMOV/AFP/Getty Images