Thirty-eight people trapped after a fire on the third-floor of the stately, Soviet-era union building burned, suffocated or jumped to their deaths. How did the victims come to be in the building and who started the fire?The seed of the violence was a football match.Local side Chernomorets were playing Metalist Kharkiv.Hardline fans - known as "ultras" - of both sides agreed to hold a joint march to support a united Ukraine.The group gathered at about 14:00 in Cathedral Square. Some were veteran supporters of Kiev's Maidan protest movement - the Maidan Self Defence Forces - and/or part of the right-wing Pravy Sektor (Rights Sector). Some were just ordinary members of the public.The marchers may have suspected trouble in a city with an ethnic Russian minority of around 30%.But as Chernomorets supporter Nadiya Yashan told Ukrainian television: "We never expected an ambush on such a scale and the police to do so little."Some of the marchers' rivals were wearing orange and black stripes on their clothing - the so-called Ribbon of St George, one of the most recognised symbols of military valour in Russia.Bogdan, who was part of the fans' march, told the BBC: "People started to walk, they were attacked by these guys in army helmets with baseball bats. Some of them had guns."The clashes appeared to begin on Grecheskaya/Hretska (Greek) Street.Eyewitness Sergey told the BBC he saw a newsflash on TV at 15:50 local time about clashes there and went to the scene."It wasn't like close, hand-to-hand combat. It was mostly throwing of pavement blocks by both sides," he said.Other reports suggested some of the activists on both sides were well-armed and well-protected - clubs, metal bars, air pistols, baseball bats and body armour, shields and helmets.A number of reports also spoke of armed protesters using the roof top of the Afina shopping centre to fire pistols and throw Molotov cocktails.Sergey spoke of a "see-saw battle" of about 15 minutes, before the "pro-separatists" started to withdraw.Over the next few hours the clashes fragmented but a key development appeared to be a move by pro-Ukrainians against a pro-Russian tent city in a square called Kulikovo Polye.Sergey said: "People started streaming toward the station, taking Zhukovskoho Street and then taking Pushkinska Street. They chanted 'Long live Ukraine!' and 'Odessa is Ukrainian!'."He said the tents in the pro-Russian camp were burning when he arrived and those there had moved to the entrance of Trade Unions House."Eventually, they were driven in," he said.By his estimate there were several thousand football fans and about 300 pro-separatists.There was hand-to-hand fighting in the building although, again, it appeared the police did little to intervene.Television pictures and reports suggest both sides were throwing Molotov cocktails.Pro-Ukrainians reported that pro-separatists were armed and firing pistols and rifles from the upper floors.Russia Today carried video of a man in a bulletproof vest shooting up at the pro-separatists in the burning building.It remains unclear how the fire started on the third floor.Pictures clearly showed pro-Ukrainians throwing Molotov cocktails towards the floor.But Sergey said he saw someone "on the third floor throw a Molotov cocktail through the closed window. However, the glass didn't break and a fire started inside".People struggled to get out of the smoke-filled floor.One survivor told Russia Today: "We couldn't go down, we were seeing people from other floors being brought down and then those rioters down there attacked them like a pack of wolves."Some people got to ledges and were helped by ambulance ladders. Some fell.One American journalist described the scene as "a lynching, pure and simple", with some people shouting "die" as people fell.There were unconfirmed reports later that Russian passports and documents from Moldova's breakaway region of Trans-Dniester were found in the building, but many believe that the victims were Ukrainian citizens.One of those who had been at the building, Anatoly, said the people were not "pro-Russian activists".He told the BBC: "We are from Odessa. It's just about Odessa, about peace. It was horror. It was annihilation of people believed to be separatists. But I am not separatist, I was born in Odessa."Over the next 48 hours, there appeared to be some respite - both sides bringing flowers to honour the dead.But few believe the violence of Odessa is over.In the aftermath, Ukraine's Prime Minister Arseniy Yatsenyuk had some angry words for the security forces, saying they were "inefficient and they violated the law".He promised a full investigation - right down to "every single police officer".But any inquiry that does try to get to the truth of what happened would have to cut through a bitter and partisan political agenda.The failings of the security forces appear to be one of the few things people agree on.(BBC)BakuDaily.Az