Odessa erupts into violence again as pro-Russian protesters vent anger against riot police outside burned-out building after 42 killed in riots between rival groups



Day of violence across Ukraine yesterday sparks fears of Russian invasion

Pro-Russian protesters gather in Odessa to mourn 42 killed yesterday

A fire in a union building there killed 37, while others were shot dead



OSCE observers held by east Ukraine insurgents released this morning



'We celebrated my birthday then they left,' says rebel leader in Slavyansk

Government continues 'anti-terror' operation in separatist-held towns







Protests have once again erupted into violence in Odessa as demonstrators vented their anger outside a building where dozens of pro-Russian protesters died in a fire last night.

Riot police struggled to contain crowds of around 2,000 chanting 'Odessa is a Russian city' as they stood in lines blocking the trade union building which was a focus of riots between rival groups.

Protesters set fire to a Ukrainian flag and turned on supporters of the Kiev government, as it looked increasingly likely that the city was turning into the newest front in Ukraine's separatist insurgency.

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New front: Pro-Russian activists attack policemen guarding the burned trade union building in Odessa today, after dozens died in street fighting between separatists and government supporters in the city last night

A Pro-Russian activist pulls the hair of a government supporter in an argument outside the burned-out building

Scuffles: Protesters try to snatch a riot policeman, as other officers look on. Police struggled to contain crowds of around 2,000 chanting 'Odessa is a Russian city' who had turned up to lay flowers for those killed last night

Meanwhile an insurgent leader in eastern Ukraine released observers from the Organisation for Security and Cooperation in Europe (OSCE) who had been held since last month.

Vyacheslav Ponomaryov confirmed that the Western observers had been released in the eastern town of Slaviansk on Saturday, and that there were no conditions for their release.

'As I promised them, we celebrated my birthday yesterday and they left. As I said, they were my guests,' he said, noting that 12 people were let go, including Europeans and Ukrainians.

This morning crowds gathered to mourn 42 people killed in the street battles in Odessa last night that ended with dozens of pro-Russian protesters trapped inside a burning building.

Even as Ukrainian military forces carried out a military offensive against separatists in the east, the riot in the Black Sea Port is now by far the most-deadly incident in Ukraine since the February uprising.

It also spread the violence from the eastern separatist heartland to an area far from the Russian frontier, raising the prospect of unrest sweeping more broadly across a country the size of France of around 45 million people.

The Kremlin, which has tens of thousands of soldiers on Ukraine's eastern border and asserts the right to invade to protect Russian speakers, said the Kiev government and its Western backers were responsible for the deaths.

'Their arms are up to their elbows in blood,' said Kremlin spokesman Dmitry Peskov.

Furious protesters drag a riot policeman to the ground: Last night's riot in Odessa, a Black Sea port just west of Crimea, is now by far the most-deadly incident in Ukraine since the February uprising

A protester aims his fist at a policeman: Violence began despite the declaration of a three-day mourning period in Odessa over the deaths in the city last night

Flower power: Demonstrators arrived at the scene of the fire to lay flowers and light candles, but tempers flared as they squared up to riot police

Divisions: Pro-Russian activists beat a pro-Kiev supporter trying to save the Ukrainian flag removed from a flagpole outside the burned trade union building

The flag burns amid the charred remains of the protest camp that pro-Russians had manned last night

Today's violence began despite the declaration of a three-day mourning period in Odessa. Demonstrators arrived at the scene of the fire to lay flowers and light candles, but tempers flared as they squared up to riot police.

Crowds surged against lines of officers who blocked access to the burned out building, while pro-Kiev supporters were attacked with clubs and manhandled as angry protesters burned Ukraine's national flag.

At the nearby hospital, residents queued up to offer blood and others tried to find out what medicine was needed so they could go out to buy it.

Firefighters evacuate an injured man outside the burnt trade union building where clashes were most intense

Hellish: The scene in Odessa late last night after security forces and pro-Kiev protesters secured the trade union building which had been a scene of protest by Russian-speaking protesters

Firefighters work at the burned Trade Union building which had been occupied by pro-Russian militants

Inferno: A grab from AP video shows people carrying a scaffolding frame through fires on the ground in Odessa

A firefighter puts out burning rubbish outside the burnt trade union building: Police said more than 130 people had been detained and could face charges ranging from participating in riots to premeditated murder

Oleg Konstantinov, a journalist covering the events for a local Internet site, said bullets had flown in the melee before the fire: 'I was hit in the arm, then I started crawling, and then got hit in the back and leg.'

The clashes ended with separatists holed up in the large Soviet-era granite-walled trade union building. Video footage showed petrol bombs exploding against its walls.

At least 37 people died in the fire. On Saturday, police raised the overall death toll in the city to 42.

It was easily the biggest death toll since about 100 people were killed in Kiev protests that toppled Ukraine's pro-Russian former president Viktor Yanukovich in February.

The Odessa bloodshed came on the same day that Kiev launched its biggest push yet to reassert its control over separatist areas in the east, hundreds of miles away, where armed pro-Russian rebels have proclaimed a 'People's Republic of Donetsk'.

The rebels aim to hold a referendum on May 11 on secession from Ukraine, similar to one staged in March in Crimea region, which was seized and annexed by Russia in a move analysts say has overturned the post-Cold War diplomatic order.

Aftermath: Ukrainian policemen stand guard outside the Trade Union building in Odessa where 37 people died in a fire that broke out during clashes between pro-Ukrainian and pro-Russian protesters last night

Vigilant: More than 41 people died in the city after gunfights broke out and the fire trapped dozens inside

Smashed: It was the first time that divisions in Odessa had spilled over into fatal violence since the crisis began

A cleaner looks at the remains of the destroyed pro-Russian protester's camp, destroyed in yesterday's clashes

A digger cleans up the remains of the barricades which had been erected outside the trade union building

As the fighting worsened, dozens of people had to be evacuated from a burning building in the Southern Port City of Odessa

At least 38 people were killed in the blaze that destroyed the trade union building in Odessa

Despite the loss of life caused by fire, Ukrainian protesters prepare Molotov cocktails for their running clashes with pro-Russian activists

A protestor walks past a pro-Russian tent camp which was set alight during clashes with Ukrainian nationalists

As the violence intensifies, Ukrainian nationalists set fire to a tent camp of pro-Russian activists

A pro Russian supporter is carried by his comrades after he was injured in running clashes with Ukrainians in Odessa

The today government said it was pressing on with the offensive in the area for a second day, and had recaptured a television tower and a security services building from rebels in Kramatorsk, a town near the rebel stronghold of Slavyansk.

'We are not stopping,' said Interior Minister Arsen Avakov in a post on Facebook. 'The active phase of the operation continued at dawn.'

Rebels in Slavyansk, their most heavily fortified redoubt, shot down two Ukrainian helicopters on yesterday, killing two crew, while unarmed protesters stalled an advance by Ukrainian troops in armoured vehicles.

Separatists said three fighters and two civilians were killed in Friday's Ukrainian advance on the town.

Vasyl Krutov, head of a government 'anti-terrorist centre' behind the operation in the east, told a news conference there was gunfire and fighting around Kramatorsk: 'What we are facing in the Donetsk region and in the eastern regions is not just some kind of short-lived uprising, it is in fact a war.'

Tyres burn at a pro-Russian activist blockade following an assault by the Ukrainian army on Kramatovsk

A man tries to put out the fire: Over the past couple of days the Ukrainian army has been assaulting pro-Russian checkpoints in and around Kramatovsk which sits on the edge of Slavyansk, a pro-Russian activist stronghold

The separatist flag of the People's Republic of Donetsk, a symbol of the separatist movement, flutters in the thick black smoke rising from the burning rubber as the offensive continues in east Ukraine

Vasyl Krutov, head of the Ukrainian government's 'anti-terrorist centre' behind the operation in the east, told a news conference there was gunfire and fighting around Kramatorsk

Ukraine: On the brink of all-out war with Russia

Arrested: Ukrainian military arrest the four men believed responsible for shooting down two helicopters, killing one pilot and a serviceman in the resulting crash The helicopter's pilot - who was injured in the crash - is carried away by pro-Russian rebels, but is said to be safe and recovering from his injuries A Ukrainian military helicopter lands at a checkpoint which troops seized in the early morning in the village of Andreevk

Under fire: A Ukrainian military helicopter lands near a Ukrainian checkpoint near the town of Slaviansk in eastern Ukraine. Two others were today shot down by pro-Russian militants An armed pro-Russian man walks past burning debris at a checkpoint in the southern Ukrainian city of Slavyansk

Missiles: The first gunship was blasted out of the sky with a surface-to-air missile over the city of Slaviansk this morning, Ukraine's Security Service said, while the other was forced to land under heavy attack

Fierce fighting: It comes as Ukrainian forces stormed the city this morning, desperate to flush out militants who have seized a number of government buildings

Armed guard: A Ukrainian soldier looks on at a Ukrainian checkpoint near the eastern town of Slaviansk - a city that has become the focus of the insurgency

But the military operation has now been overshadowed by the unprecedented violence in Odessa, a vibrant multi-ethnic port city that has seen some support for separatists but nothing like the riots that erupted on last night.

Despite the video evidence to the contrary, Kiev blamed the pro-Russian protesters for the fire tragedy.



The Interior Ministry said they had attacked government supporters before retreating to the trade union headquarters, from where they opened fire on the crowd and threw out the petrol bombs that caused the blaze.

Odessa is located in the southwest of Ukraine, far from the eastern areas held by the rebels and far from the Russian frontier where Moscow has amassed troops.

But it is close to Moldova's Transdniestria region, where Russia also has troops.

The spread of violence to Odessa expands the zone of unrest across the breadth of southern and eastern Ukraine.

'Today we Ukrainians are constantly being pushed into confrontation, into civil conflict, toward the destruction of our country to its heart. We cannot allow this to happen and we must be united in the fight against a foreign enemy,' said acting President Oleksander Turchinov.