Vladimir Skorobagach, deputy of the Kharliv city council, reacts after being thrown by activists into a garbage container during a protest for the resignation of the Kharkiv's mayor Gennady Kernes outside the city council in Kharkiv, December 24, 2014. (Photo by Reuters/Stringer)

An Ukrainian serviceman checks his helmet at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen sit atop an armored personnel carrier (APC) at a military base in the town of Kramatorsk, eastern Ukraine, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

An Ukrainian serviceman guards at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian serviceman sits atop an armored personnel carrier (APC) at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

An Ukrainian military convoy is pictured through the shooting spot of an armored personnel carrier (APC) on the road from Kramatorsk to Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen patrol an area near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen stand guard at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian serviceman guards as his comrades check a civilian transport near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A woman speaks with Ukrainian serviceman in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian serviceman guards his position in the eastern Ukrainian town of Debaltseve in Donetsk region December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A woman with a child walks past Ukrainian servicemen in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian serviceman patrols an area near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen patrol an area near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen patrol an area near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

An Ukrainian serviceman rides on an armored personnel carrier (APC) as he patrols an area near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen guard the street in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen ride on an armored personnel carrier (APC) at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A man walks past Ukrainian servicemen in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen stand near a building damaged during fighting between pro-Russian rebels and Ukrainian government forces in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian military convoy is pictured through a barbed wire fence at a military base in the town of Kramatorsk, eastern Ukraine, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian serviceman plays with a dog as he and his comrade patrol the street in the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen sit atop an armored personnel carrier (APC) at a military base in the town of Kramatorsk, eastern Ukraine, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

Ukrainian servicemen sit atop an armored personnel carrier (APC) at a military base in the town of Kramatorsk, eastern Ukraine, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian serviceman keeps watch from an armored personnel carrier (APC) as he patrols the road in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A Ukrainian serviceman walks at a checkpoint near the eastern Ukrainian town of Debaltseve in Donetsk region, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)