More than 50 pro-Russian rebels were killed in an unprecedented assault by Ukrainian government forces, which raged into a second day on Tuesday after a newly-elected president vowed to crush the revolt in the east once and for all.
Reuters journalists counted 20 bodies in combat fatigues in one room of a city morgue in Donetsk. Some of the bodies were missing limbs, sign that the government had brought to bear overwhelming firepower against the rebels for the first time.
"From our side, there are more than 50 (dead)," the prime minister of the rebels' self-styled Donetsk People's Republic, Alexander Borodai, told Reuters at the hospital.
Russian President Vladimir Putin, who has declared Moscow's right to intervene to protect Russian speakers in Ukraine, demanded an immediate halt to the offensive. Moscow also said it would not consider a visit by Poroshenko for any talks.
Until now, Ukrainian forces have largely avoided direct assaults on the separatists, in part out of what they say is fear of precipitating an invasion by tens of thousands of Russian troops massed on the border.
But the government in Kiev appears to have interpreted Poroshenko's big election victory - he won more than 54 per cent of the vote in a field of 21 candidates, against 13 per cent for his closest challenger - as a mandate for decisive action.
After rebels seized the Donetsk airport on Monday, Ukrainian warplanes and helicopters strafed them from the air and paratroopers were flown in as part of the assault.
Shooting carried on through the night and on Tuesday the road to the airport bore signs of fighting. Heavy machinegun fire could be heard in the distance in mid-morning.
On the highway to the airport, a truck - the kind that rebels have used to ferry dozens of fighters across the region - had been obliterated by machinegun fire. Blood was sprayed across the road and splattered as far away as a billboard seven meters above.
"The airport is completely under control," Interior Minister Arsen Avakov told journalists in the capital Kiev. "The adversary suffered heavy losses. We have no losses," he added.
"We'll continue the anti-terrorist operation until not a single terrorist remains on the territory of Ukraine," First Deputy Prime Minister Vitaly Yarema said on the margins of a government meeting.
Borodai, the rebel prime minister, also said the airport was now under government control.
A hockey stadium in the city had been set ablaze, but the fire was put out.
Lethal force
The battle marks the first time the government has unleashed the full lethal force of its aircraft and ground troops directly at the Donetsk rebels, a group of local volunteers and shadowy outsiders led by a Muscovite that Kiev and Western countries say is a Russian military intelligence agent.
In a news conference on Monday after his decisive election victory, Poroshenko promised to invigorate the government's previously ineffective "anti-terrorist" campaign, saying it ought to be able to put down the revolt within hours, rather than months. He also said there could be no negotiations with rebels he described as terrorists, bandits and pirates.
The intensification of the Ukrainian campaign is a direct challenge to Putin, who responded to the overthrow of a pro-Russian president in Kiev in February by declaring that Russia has the right to invade Ukraine to defend Russian speakers and swiftly annexing Ukraine's Crimea peninsula.
The Kremlin said on Tuesday Putin had called for an end to the Ukrainian military campaign and for dialogue between Kiev and the separatists. Putin was speaking in a telephone call with Italy's prime minister, his first reported comments on Ukraine since Sunday's election.
For two months Putin has massed troops on the frontier, while pro-Russian gunmen took control of towns and cities in the east and the Kiev government seemed powerless to stop them.
Moscow's consistent message was that the government in Kiev, which took power after President Viktor Yanukovich fled from an uprising by pro-European demonstrators, was an illegitimate "fascist junta" and that Russian speakers were in danger.
But Poroshenko's margin of victory undermines that message, even though separatists succeeded in blocking the vote in the two eastern provinces they hold, keeping 10 per cent of the overall national electorate away from the polls.
Poroshenko has served as a government minister both under Yanukovich and his Ukrainian nationalist rivals, giving him a reputation as a pragmatist capable of bridging Ukraine's pro- and anti-Russian divide.
The separatists have repeatedly called for Putin to send his forces to aid them, and Putin has followed the annexation of Crimea by turning the protection of Russians in other former Soviet republics into a central theme of his rule. Last month Putin referred to eastern Ukraine as "New Russia".
But in the run-up to the election his words had become more accommodating. On the eve of the vote, he promised to accept the will of the Ukrainian people. On Monday his government said it was prepared to work with Poroshenko, although it called for him to call off the military campaign.
Western countries say they do not trust Putin's promises not to interfere, and that he announced he would withdraw his troops repeatedly without doing so.
The United States and European Union have imposed limited sanctions on a few dozen Russian individuals and small firms but have said they would take much stronger action, including measures against whole swathes of Russian industry, if Moscow interfered in Sunday's Ukrainian election.
In another sign of confidence since Poroshenko's election, Kiev pressed a claim on Tuesday for more than $1 billion from Russia's natural gas export monopoly Gazprom, for gas it said Moscow had "stolen" when it annexed Crimea.
Russia has threatened to switch off Ukraine's gas from June 3 unless it pays Gazprom up front for supplies. Moscow wants to charge Kiev far more for gas than it charges European countries. Kiev wants a lower price. A gas cut-off could hit onward shipments to Western Europe, some of which transit Ukraine.
Reuters journalists counted 20 bodies in combat fatigues in one room of a city morgue in Donetsk. Some of the bodies were missing limbs, sign that the government had brought to bear overwhelming firepower against the rebels for the first time.
"From our side, there are more than 50 (dead)," the prime minister of the rebels' self-styled Donetsk People's Republic, Alexander Borodai, told Reuters at the hospital.
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The government said it suffered no losses in the assault, which began with air strikes hours after Ukrainians overwhelmingly voted to elect a 48-year-old billionaire confectionery magnate Petro Poroshenko as their new president.
Russian President Vladimir Putin, who has declared Moscow's right to intervene to protect Russian speakers in Ukraine, demanded an immediate halt to the offensive. Moscow also said it would not consider a visit by Poroshenko for any talks.
Until now, Ukrainian forces have largely avoided direct assaults on the separatists, in part out of what they say is fear of precipitating an invasion by tens of thousands of Russian troops massed on the border.
But the government in Kiev appears to have interpreted Poroshenko's big election victory - he won more than 54 per cent of the vote in a field of 21 candidates, against 13 per cent for his closest challenger - as a mandate for decisive action.
After rebels seized the Donetsk airport on Monday, Ukrainian warplanes and helicopters strafed them from the air and paratroopers were flown in as part of the assault.
Shooting carried on through the night and on Tuesday the road to the airport bore signs of fighting. Heavy machinegun fire could be heard in the distance in mid-morning.
On the highway to the airport, a truck - the kind that rebels have used to ferry dozens of fighters across the region - had been obliterated by machinegun fire. Blood was sprayed across the road and splattered as far away as a billboard seven meters above.
"The airport is completely under control," Interior Minister Arsen Avakov told journalists in the capital Kiev. "The adversary suffered heavy losses. We have no losses," he added.
"We'll continue the anti-terrorist operation until not a single terrorist remains on the territory of Ukraine," First Deputy Prime Minister Vitaly Yarema said on the margins of a government meeting.
Borodai, the rebel prime minister, also said the airport was now under government control.
A hockey stadium in the city had been set ablaze, but the fire was put out.
Lethal force
The battle marks the first time the government has unleashed the full lethal force of its aircraft and ground troops directly at the Donetsk rebels, a group of local volunteers and shadowy outsiders led by a Muscovite that Kiev and Western countries say is a Russian military intelligence agent.
In a news conference on Monday after his decisive election victory, Poroshenko promised to invigorate the government's previously ineffective "anti-terrorist" campaign, saying it ought to be able to put down the revolt within hours, rather than months. He also said there could be no negotiations with rebels he described as terrorists, bandits and pirates.
The intensification of the Ukrainian campaign is a direct challenge to Putin, who responded to the overthrow of a pro-Russian president in Kiev in February by declaring that Russia has the right to invade Ukraine to defend Russian speakers and swiftly annexing Ukraine's Crimea peninsula.
The Kremlin said on Tuesday Putin had called for an end to the Ukrainian military campaign and for dialogue between Kiev and the separatists. Putin was speaking in a telephone call with Italy's prime minister, his first reported comments on Ukraine since Sunday's election.
For two months Putin has massed troops on the frontier, while pro-Russian gunmen took control of towns and cities in the east and the Kiev government seemed powerless to stop them.
Moscow's consistent message was that the government in Kiev, which took power after President Viktor Yanukovich fled from an uprising by pro-European demonstrators, was an illegitimate "fascist junta" and that Russian speakers were in danger.
But Poroshenko's margin of victory undermines that message, even though separatists succeeded in blocking the vote in the two eastern provinces they hold, keeping 10 per cent of the overall national electorate away from the polls.
Poroshenko has served as a government minister both under Yanukovich and his Ukrainian nationalist rivals, giving him a reputation as a pragmatist capable of bridging Ukraine's pro- and anti-Russian divide.
The separatists have repeatedly called for Putin to send his forces to aid them, and Putin has followed the annexation of Crimea by turning the protection of Russians in other former Soviet republics into a central theme of his rule. Last month Putin referred to eastern Ukraine as "New Russia".
But in the run-up to the election his words had become more accommodating. On the eve of the vote, he promised to accept the will of the Ukrainian people. On Monday his government said it was prepared to work with Poroshenko, although it called for him to call off the military campaign.
Western countries say they do not trust Putin's promises not to interfere, and that he announced he would withdraw his troops repeatedly without doing so.
The United States and European Union have imposed limited sanctions on a few dozen Russian individuals and small firms but have said they would take much stronger action, including measures against whole swathes of Russian industry, if Moscow interfered in Sunday's Ukrainian election.
In another sign of confidence since Poroshenko's election, Kiev pressed a claim on Tuesday for more than $1 billion from Russia's natural gas export monopoly Gazprom, for gas it said Moscow had "stolen" when it annexed Crimea.
Russia has threatened to switch off Ukraine's gas from June 3 unless it pays Gazprom up front for supplies. Moscow wants to charge Kiev far more for gas than it charges European countries. Kiev wants a lower price. A gas cut-off could hit onward shipments to Western Europe, some of which transit Ukraine.