A crisp autumn morning in Belgrade last Sunday: Activists gather for what they hope will be the city's first successful gay pride.
They walk through the streets, guarded by police - a chance to express themselves in a society still riven by homophobia.
But as they follow their short route, trouble brews in several parts of the city.
Hundreds of anti-gay protesters have congregated, hurling stones and petrol bombs at armed police, who respond with tear gas and rubber bullets. More than 100 officers are injured in hours of street battles.
Two days later, Serbia's Euro 2012 qualifier against Italy in Genoa: Hooded Serbian fans throw flares on to the pitch and threaten the Serbian goalkeeper.
Italian riot police intervene. The game is cancelled and more than 30 fans arrested.
Serbia, still emerging from the darkness of the Yugoslav wars and diplomatic isolation in the 1990s, now seemingly at war with itself.
"These groups are extremely right-wing and clearly have a political goal", says Zoran Dragisic, a professor of security studies in Belgrade.
"They are close to organised crime and are sending a message that they don't want Serbia to join Nato and the EU.
"If Serbia becomes a member of the EU, they can't perform their criminal activities in the same way. I am worried that this violence could be very dangerous for Serbia's European ambitions".
Serbia has long grappled with football-related violence.
Paramilitary groups in the 1990s forged close links with aggressive supporters' clubs.
Last year, Brice Taton, a young Frenchman who had travelled to Belgrade for an away match, was beaten to death by a Serbian gang in the centre of the city.
But this week, football hooligans and ultra nationalist groups came together in a toxic mix that has thrown Serbia into a bout of soul-searching.
One newspaper headline read "Shame on Serbia". Another screamed "The Death of Serbia."
"This is related to problems in our past because most of these people are young and grew up during the wars," says Slobodan Homen, Serbia's deputy justice minister.
"We're now paying the price for not caring for our young people enough."
He is adamant that the government will take a firm line, including banning several groups, but believes the reaction should not simply be punitive.
"The priority should be the education system and the family," he says.
"We need to explain to our young people that we are very definitely heading for European integration, otherwise every couple of years, we will have this kind of violence".
I ask whether he is confident these groups can be defeated.
"A hundred per cent," he replies. "This is the end of them. I think we will never again face the kind of violence we've seen this week."
But the perpetrators believe they have the upper hand, and have pledged to step up their actions.
Boris Bratina is a member of one of the biggest organisations, 1389 - a reference to a momentous battle in Serbian history.
We talk in the group's tiny, dark office on the outskirts of Belgrade. The walls are adorned with "No EU" signs, Orthodox Christian icons and photographs.
Among the latter is a print of the former Bosnian Serb leader, Radovan Karadzic, currently on trial in The Hague on charges of genocide. The word "hero" has been scrawled beneath his image.
Boris admits members of his group were at the gay pride protests. I ask whether they were involved in the violence.
"Oh, no," he says, before stammering: "Er... um... of course they had to defend themselves against aggressive policemen.
"The gay parade was a provocation against Serbian people."
He goes on to make allegations about homosexual behaviour.
So is it justified to throw rocks at policemen and smash bus shelters? I ask.
"Of course it is," he replies. "This was just a reaction of angry people."
The official investigation into the incidents in Italy suggests members of 1389 were there too, but he denies it.
"I would like them to be members, because they acted the way we would like," he says.
"We were saying in Italy that we don't want to be a member of the EU."
How far will they go to achieve their goals?
"There will be much more violence than on Sunday," he says. "We will call on civil disobedience to push out this banana government."
I tell him the authorities say they will crush the groups. He sniggers: "Let them. We are unconquerable."
And yet when I ask him how many members 1389 boasts, he tries to evade the question.
"Maybe 2,000," he ventures finally.
So against a population of over seven million and the full state machinery, how can he possibly claim to represent the majority of public opinion?
"Everybody basically supports 1389," he says, somewhat spuriously.
This week has profoundly shocked a population trying hard to move away from the 1990s and present a changed, democratic Serbia.
Those behind the violence are an extreme minority but the images have undoubtedly tarnished the country's image.
Serbia is a proud nation but the challenge now is to replace violent nationalism with peaceful patriotism.
For now, there is still the fear that renegade elements from Serbia's past could yet hold this country up on its path to a European future.