Ongoing coverage of the confrontation between Russia, Vladimir Putin and the West over Russia’s aggression in Crimea and Ukraine.
The Kremlin's latest high-profile prisoner is Nadiya Savchenko, Ukraine's first female pilot and a symbol of resistance for many in her home country.
Both sides saw strategic value in controlling the airport, but the fighting has rendered the airport unusable.
The pullback was supposed to have started more than a week ago under a peace deal agreed on earlier this month.
The State Department criticized Russia's "unacceptable" refusal to release Ukrainian pilot Nadiya Savchenko, who has been on hunger strike for almost 11 weeks.
Prime Minister Arseniy Yatsenyuk said Tuesday that Russia was not withdrawing heavy weapons from the east of his country
Arseniy Yatsenyuk said he does not believe Ukraine can go it alone to bring about a peaceful resolution to his country's divisions.
Vladimir Putin called the prospect of all-out war between Russia and Ukraine "unlikely."
What started out as a local protest over presidential overreach has grown into a chaotic war between Ukraine and pro-Russian separatists, all within a calendar year.
The swap of 139 Ukrainian troops for 52 rebels is part of a process intended to usher peace to the east.
Secretary of State John Kerry was in London on Saturday to meet with allies over possible new sanction on Russia.
The Russian president declared "No one should have the illusion that they can gain military superiority over Russia."
America's European allies sleepwalked into the conflict with Russia in Ukraine, according to a report by British lawmakers.
Russian President Vladimir Putin appears to be eyeing Abkhazia and South Ossetia, two separatist territories that split from Georgia in the 1990s.
The U.S. has deployed 12 "tankbuster" A-10 Thunderbolt II aircraft and 300 airmen to Germany's Spangdahlem Air Base.
Sasha Grey, who is very much alive and not taking part in the Ukrainian conflict, is not at all comfortable with her latest role.
Ukrainian troops held out in the encircled town for three days before the government pulled them out on Wednesday.
Ukrainian military column arrived in government-held Artemivsk after pulling out of strategic town being contested with pro-Russian rebel forces.
Some pro-government forces began on Wednesday to pull out of the rebel-besieged east Ukrainian town of Debaltseve.
In better times, a Palace of Culture serves as a community center for Ukrainian residents, but in times of war, it's a bomb shelter.
Pro-Russian rebels and Ukrainian forces fought street-to-street in Debaltseve on Tuesday and refused to pull back their heavy guns.
News crews covering Ukrainian ceasefire had a narrow escape after shelling near Debaltseve sparked gas fire. One crew member was injured by shrapnel.
A government-held town in Ukraine came under shelling a day after the start of a ceasefire that Russian-backed separatists say does not apply there.
Ukraine said pro-Russian rebels had shelled Ukrainian positions since a ceasefire came into effect Sunday, but the truce was generally being observed.
Both sides accused the other of fresh attacks after the cease-fire went into effect one minute after midnight Sunday local time.
Ukrainian President Petro Poroshenko declared he would consider imposing martial law if the fighting does not abate.
Seven Ukrainian service personnel have been killed and 23 wounded in 24 hours despite a planned cease-fire worked out at a four-power peace deal.
Eight troops were killed despite Ukraine peace deal and looming cease-fire deadline, military officials said.
World leaders announced on Thursday a cease-fire to the violence in eastern Ukraine that has claimed more than 5,000 lives.
Ukraine's war is escalating and hopes for peace are fragile, Bill Neely reports.
Fighting raged in eastern Ukraine ahead of crucial peace talks between Russia's Vladimir Putin and Ukraine's president on Wednesday.
At least two people reported to have died after sustained shelling hit a city-to-city bus station in the Ukrainian rebel stronghold.
Seven civilians were killed in rocket strikes in Ukraine as President Obama discussed the worsening violence in a phone call to the country's leader.
Dramatic scenes as kitchen workers scrambled for cover as rockets fell on Pervomaisk in mainly rebel-held Ukrainian Luhansk region.
A powerful explosion rocked a chemical plant and set it on fire Monday outside the separatist stronghold of Donetsk in eastern Ukraine.
The leaders of Russia, Ukraine, Germany and France agreed to meet in Belarus on Wednesday to try to broker a peace deal for Ukraine amid escalating violence.
The United States will send more aid to Ukraine as part of that country's fight against Russia, Secretary of State John Kerry told "Meet the Press."
Kerry's remarks came as Germany announced another high-level summit aimed at stemming the crisis in Ukraine.
Petro Poroshenko sought defensive weapons from the West as mediators sought to find momentum for a peace deal Saturday.
The U.S. has vowed to back Ukraine against Russian-backed rebels, while Germany hopes to broker a cease-fire.
In an exclusive interview to air Sunday on Meet the Press, Secretary of State John Kerry says he has "no doubt" that additional assistance will be going to Ukraine.
German Chancellor Angela Merkel said Saturday it's uncertain whether a flurry of diplomacy aimed at calming the crisis in Ukraine will succeed.
There's a new diplomatic push to stop the violence, and the violence is getting worse.
Joe Biden warned Friday that Russia "cannot be allowed to redraw the map of Europe" and that Ukraine was suffering a "military onslaught" from Moscow.
The leaders of Germany and France are expected to take peace proposals to Moscow on Friday in a dramatic initiative to end a conflict in Ukraine.
The United States is looking for a diplomatic resolution to the crisis in Ukraine, Secretary of State John Kerry said.
As the White House decides whether to arm Ukrainian troops, the commander of the U.S. Army in Europe says "just providing weapons is not a strategy."
Lt. Gen. Ben Hodges, commander of U.S. Army in Europe, said he expected a diplomatic solution to Ukrainian crisis, but conditions are not yet right.
The town of Vuhlehirsk's capture would be a setback for the Ukrainian government after an attempt to revive peace talks with separatists collapsed.
A shell landed near a hospital in the east Ukrainian rebel-controlled city of Donetsk on Wednesday, killing three people.
Five Ukrainian government troops were killed and dozens more wounded in intensified fighting with pro-Russia rebels near the town of Debaltseve.
The New York Times reported that administration and military officials are edging toward providing "defensive" arms to Ukrainian forces.
Both sides blamed each other for the failure of the peace talks, aimed at ending a conflict that has claimed at least 5,000 lives.
Speaking from his hospital bed, Russian fighter Artur described the moment he came under attack by Ukrainian forces.
The allies are nervous about Russian intentions following Moscow's annexation of Ukraine's Crimea region.
Travel restrictions by the Ukrainian government are impeding war-weary civilians from fleeing relentless shelling in the rebel stronghold of Donetsk.
Two blasts from artillery shells in residential area of separatist-run Donetsk, in eastern Ukraine, left at least six people dead Friday morning.
A separatist advance last week in eastern Ukraine appears to have buried the frequently violated truce, leading to a sharp increase in casualties.
Seven Ukrainian servicemen were killed and 24 wounded as fighting in the east of the country reached its worst level since last September's ceasefire.
Rocket fire kills at least 30 people in the Ukrainian city of Mariupol in the southeastern region of the country Saturday. The incident occurred just one day after Russian rebels rejected a peace deal with Ukraine.
Fifteen people were killed in shelling in the east Ukrainian city of Mariupol on Saturday, Ukraine's interior ministry said as violence escalated.
NATO's military commander Gen. Philip Breedlove said alliance intends to re-establish contact with Russian counterparts, after months of tension over Ukraine.
An "appalling" attack on a bus stop that killed at least eight civilians was likely a violation of humanitarian law, Amnesty International said.
Shell or mortar round hit trolleybus at stop in rebel-controlled Donetsk in eastern Ukraine. Eye witnesses counted at least six dead in and around bus.
Pro-Russian separatists renewed attacks on Ukrainian forces at an airport complex in the east on Monday.
Aerials shows the destroyed Donetsk Airport hit by shelling during fighting between pro-Russian separatists and Ukrainian government forces.
The army's offensive at the airport brought the fighting close to the city of Donetsk itself, center of a pro-Russian separatist rebellion.
Interpol issued a wanted notice for ousted Ukrainian president Viktor Yanukovych, alleging various corruption charges.
It is not known exactly how many prisoners are currently held by the two sides, but Ukraine's military said around 600 Ukrainians were in rebel hands.
Seasoned Chechen soldiers are supporting pro-Russian rebels in eastern Ukraine.
Former Soviet leader Mikhail Gorbachev called for a U.S.-Russia summit to be convened to prevent a deep freeze in Moscow's relations with the West
U.S. plans for missile defense systems in Europe were a threat to Russia, President Vladimir Putin said, and Moscow would increase non-Western ties.
Amateur video purportedly showed Grad rocket launcher firing from near apartment block in Donetsk, pro-Russian separatist city in Ukraine.
Many residents in Ukraine's city of Donetsk are struggling on with their lives amid a conflict in which one million people have fled their homes.
French President Francois Hollande delayed his decision on whether to deliver the first of two Mistral helicopter carriers ordered by Russia.
Ukrainian President Petro Poroshenko was shouted at by angry relatives of the 100 protesters killed in Kiev's "Euromaidan" revolution at a ceremony to pay tribute to the victims.
Ukrainian President Petro Poroshenko was shouted down by angry relatives of 100 protesters killed in Kiev's "Euromaidan" revolution at a ceremony.
As Ukraine's pro-democracy movement gave way to conflict in the nation's east, musicians created works voicing the tumult being felt, a film shows.
NATO Secretary-General Jens Stoltenberg said a military buildup was taking place both inside Ukraine and on the Russian side of the border.
While the world's leaders meet in Australia, Russia has denied escalating renewed fighting between Ukraine and pro-Moscow rebels.
With a cease-fire between Ukraine and pro-Russian separatists barely holding, Ukrainian leaders are taking steps to end certain services in the east.
Ukrainian military cadets release pigeons and balloons during an initiation ceremony in Orthodox Monastery of Caves in Kiev, Friday.
The cease-fire in eastern Ukraine is all but dead, according to Ukraine's representative to the Organisation of Security and Co-operation in Europe.
Multiple columns of Russian tanks, artillery and air defense systems have poured into Ukraine in the past two days, U.S. Gen. Philip Breedlove said.
Artillery shelling occurs almost daily around the strategically important Donetsk airport, despite the cease-fire,
Much more than a local election has been won or lost in Eastern Ukraine.
Former electrician Alexander Zakharchenko was sworn-in as president of the breakaway pro-Russian Donetsk People's Republic in highly symbolic ceremony
Washington warned Russia of unspecified "costs" if it recognizes Alexander Zakharchenko as head of the separatist "Donetsk People's Republic."
Pro-Russian rebels voted to set up a separatist leadership in eastern Ukraine Sunday, aiming to take the war-torn region closer to Russia.
Tomasz Siemoniak said the troops are needed in the east because of the conflict in neighboring Ukraine.
Poroshenko thanked voters for backing a "democratic, reformist, pro-Ukrainian and pro-European majority."
President Petro Poroshenko's party has campaigned on an ambitious reform agenda and is expected to get the largest share of the vote.
Ukraine's pro-Western president called Sunday's snap vote to secure increased legitimacy for Kiev's leadership in the face of pressure from Russia.
Vladimir Putin accused the U.S. on Friday of endangering global security by imposing a "unilateral diktat" on the rest of the world.
Volodymyr Borysenko, an election candidate allied to Ukraine’s prime minister, came under a gun and grenade attack as he left his home late Monday.
A powerful blast shook Donetsk in east Ukraine with the shock felt miles away. The blast occurred at a rubber processing factory in a rebel-held area.
Talks over Ukraine between Russia and European governments on Friday were "full of misunderstandings and disagreements," the Kremlin said.
Russian President Vladimir Putin and Ukrainian leader Petro Poroshenko will look to fix a broken ceasefire in eastern Ukraine during a summit Friday.
Shelling continued at the Donetsk International Airport as fighting escalated between Ukrainian forces and pro-Russian separatists on Thursday.
A member of topless feminist group Femen was convicted of exhibitionism Wednesday after attacking a statue of Vladimir Putin at a wax museum.
In an interview with CNBC, Dmitry Medvedev said President Barack Obama's comments at the U.N. were "like some kind of mental aberration."