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.
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.
A volunteer gives humanitarian aid to residents of Popasna, Ukraine, on Saturday, February 28.
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.
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.
Pro-Russian rebels stationed in Horlivka launch missiles on Wednesday, February 18.