He was a former punk rocker called "the Bonebreaker." He was known for organizing underground bare-knuckle boxing matches. And he was one of Russia's most high-profile antiracism activists.

Ivan Khutorskoi had survived a few attacks by militant nationalists -- once with a knife, once with a razor, and once with a screwdriver. But the burly 26-year-old's luck ran out on November 16 when he was shot dead in the stairwell of his apartment on the outskirts of Moscow.
A day later, Khutorskoi's allies in Russia's growing antifascist movement, known as "Antifa," struck back.

Scores of Antifa activists descended on the headquarters of the pro-Kremlin youth group Young Russia -- which Antifa members say has ties to extreme nationalists. The activists smashed windows with metal rods, threw stones and garbage, and clashed with Young Russia members.

Observers say they expect the violent struggle between Antifa activists and militant nationalist youths to escalate:

"This isn't a game. What is going on between Nazis and Antifa is a full-fledged war," Ilya Yashin, a youth leader with Solidarity, the anti-Kremlin group whose founders include Garry Kasparov, tells RFE/RL's Russian Service.

"At this time it is like a partisan war with guerrillas fighting in an urban jungle. But it is a real war nonetheless."

This emerging war, analysts say, pits two highly politicized and increasingly militant youth camps, each with starkly different visions of Russia's future, against each other.

The nationalist groups, whose ranks number in the tens of thousands, say they want a "Russia for Russians" and have long been targeting foreigners, ethnic minorities, and antiracism activists with brutal -- and often lethal -- attacks.

The Antifa activists, whose numbers are considerably smaller, have a more cosmopolitan vision for their country and have forged ties with antifascist activists abroad.

In the past they employed a defensive strategy, simply seeking to protect minorities from attacks.

But as their ranks have grown, they have increasingly become targets themselves.

"A few years ago, they couldn't even fight. Now no antifascist leader can feel safe when they enter their apartment block. Any one of them can get a bullet in the head or suffer a blow with a metal pipe," Yashin says.

Rights Activists Concerned

But recently, Antifa began taking the fight to their enemy, staging their own attacks against known nationalists.

And that is a prospect that has disturbed some veteran human rights activists, who agree with Antifa's antiracism agenda and message -- but not their recent turn toward violence.

On November 19, a group of human rights luminaries -- including Lyudmila Alekseyeva of the Moscow Helsinki Group, Aleksandr Cherkasov of Memorial, Lev Ponomaryov of For Human Rights, and the liberal clergyman Gleb Yakunin -- issued an appeal to Antifa "not to succumb to provocations, to renounce violence, and not to become a bargaining chip in a dirty game."

They warned that violent retaliations against nationalists would "not stop the terror" from militant nationalists, but instead would "give law enforcement authorities a pretext for new repressions," which may have been "the goal of provocateurs."

"There are many other ways for them to show that they are against racism. I personally don't like fighting the battle this way," Alekseyeva tells RFE/RL's Russian Service, referring to the attack on Young Russia's headquarters.

"This doesn't mean that we will stop supporting the antifascist activists. But we will not support acts like this."

Links To The State

Antifa activists say the nationalists have been violently attacking them for years, and have the tacit support of law enforcement and many in Russia's political leadership. In such circumstances, Antifa members say, they have no choice but to defend themselves.

The assault on Young Russia's headquarters, they say, was aimed at the group's leader, State Duma Deputy Maksim Mishchenko, a member of the dominant United Russia faction who sits on the Duma's Youth Affairs Committee. The activists say Mishchenko has ties to the radical ultranationalist group Russky Obraz, which they say was behind Khutorskoi's killing.

"This was the correct thing to do. It was a warning. Antifascists simply came to express their dissatisfaction that State Duma Deputy Maksim Mishchenko is supporting Russky Obraz," an Antifa activist who refused to give his name told RFE/RL's Russian Service.

Mishchenko admits that he and Young Russia have had ties with Russky Obraz in the past -- including a joint trip to Serbia and Kosovo and cooperation on legislation on illegal immigration and economic crimes -- but denies giving the group any explicit support:

"The accusations that we are their patrons are simply silly. It's nonsense," Mishchenko said.

A spokesman for Russky Obraz, Yevgeny Valayev, told the Associated Press that the group had cooperated with Mishchenko on several initiatives, including an ultranationalist march in Moscow early this month.

Not Just Punks

There are no precise figures on how many antifascist activists there are in Russia. Experts at the Moscow-based Sova Center, which monitors hate crimes, say their numbers are growing but are still far shy of the tens of thousands who belong to militant nationalist organizations.

"These aren't just punks who go to concerts. They are socialized and politicized. The antifascist movement simply can't make peace with the fact that Nazism is growing," Ponomaryov says.

Khutorskoi is scheduled to be buried on November 21, but his friends and family are keeping the details quiet out of fear that the funeral could draw attacks from nationalist groups.

A social worker by profession, Khutorskoi provided security for Antifa events. He also sometimes guarded human rights lawyer Stanislav Markelov.

He was not present, however, at Markelov's press conference in January, after which the lawyer was shot dead, together with "Novaya gazeta" journalist Anastasia Baburova. Earlier this month, police arrested two militant nationalists in connection with the killings.

Ponomaryov says Russia's rulers, who have often turned a blind eye to ethnic violence and have tacitly encouraged nationalism and xenophobia in pro-Kremlin youth groups, bear a lot of responsibility for the current state of affairs.

"If the authorities would oppose the resurrection of Nazism, then this standoff would not be so aggressive," Ponomaryov says.

"The less the authorities deal with this problem, the more that pro-Kremlin groups like Young Russia will use nationalism and xenophobia to gain support. And the more antifascist groups fighting against this will feel threatened, because they are alone."

RFE/RL's Russian Service contributed to this report