By Thomas Grove and Steve Gutterman

MOSCOW, May 13 (Reuters) - They beat him. They shoved beer bottles in his anus. They tried to set him on fire. Then they crushed his head with a heavy stone.

A 23-year-old man in Russia's southern city of Volgograd was tortured and killed after revealing he was gay during a drinking session last Thursday night, investigators said, taking a rare step by linking a murder to homophobia.

The victim's 22-year-old friend and a former convict aged 27 were detained for the attack, which gay rights activists say is a brutal example of rising violence against homosexuals in the year since President Vladimir Putin latched on to family values to shore up support in Russia's largely conservative society.

Along with a planned new law banning the spread of gay "propaganda" among minors, Putin has also overseen a religious revival that aims to give the Orthodox Church, whose leader has suggested that homosexuality is one of the main threats to Russia, a more public role as a moral authority.

Gay rights campaigner Nikolai Alexeyev said the draft law, which could be passed this month, and Putin's criticism of gays for failing to help Russia's population decline, amounted to "a call to action for the scum who committed this crime".

"It essentially gives these people carte blanche to commit such crimes," he said of the law, a local version of which is already in place in Russia's second city of St Petersburg.

The number of documented cases of violence against gays in Russia is low. Rights group Sova, which tracks extremist violence, says violence against gays has risen sharply - but from only three recorded attacks in 2011 to 12 in 2012.

But there are no official figures on anti-gay crime in Russia, and gay rights campaigners say the numbers available mask the true number of attacks on gays, lesbians, bisexual and transgender people. Most go unreported, or are not classified as such by the police.

"Such crimes are committed around Russia every day," Alexeyev said. "As a rule, all these crimes are categorised as something ordinary - they argued over a bottle of vodka, or there was 'personal animosity'. The real motive of hate is not mentioned."

Lawyer Maria Kozlovskaya, who works with the LGBT community, points to an internet poll late last year that found 15 percent of about 900 LGBT people surveyed in Russia said they had been physically attacked at least once in the previous 10 months.

THE MUZHIK RULES

Gay activists say the government's conservative policies offer "unspoken support" for violence. This, they say, could even have made the suspects in the Volgograd murder describe their victim as gay to win some sympathy.

"I think they may want to say, 'Look, we killed a gay person and not a regular, normal person'," Alexeyev said.

Andrei Gapchenko, a senior investigator in Volgograd, said one of the suspects had admitted torturing the victim.

"Four young people were drinking ... And one of them already knew, he'd heard from others, that he (the victim) was of an untraditional sexual orientation," he said by telephone.

"He asked him the question and the victim said yes .. After that, one of them hit him, he fell to the floor, and then they brutally beat him, set fire to the clothes he was wearing, slashed his anal area and then stuck three bottles in there, again beat him and then threw a 20-kg stone onto his head."

He said violent crime was not unusual in Volgograd, but that homophobic crime was.

Many Russian men like to be seen as a "muzhik" - which literally means "peasant" but now connotes a tough, single-minded man with conservative ideals who dominates his household.

Such men have been part of Putin's power base since he was first elected president in 2000. He has sought to rally their support since returning to the presidency a year ago, especially after protests against his return to the post after four years as premier, mainly by middle-class liberals in big cities.

As support for same-sex marriage and other forms of equality increases in the West, Russian gays say they face shrinking freedoms and rising violence.

"Since Putin's return to power it's got worse," said Igor Yasin, one of about 20 protesters who were attacked outside the Russian parliament in January when they tried to demonstrate against the planned bill on gay propaganda.

"Things were always difficult, but they only started getting dangerous about a year ago," said Yasin, a 32-year-old employee at a state-owned television station.

Yasin's face was bloodied after being punched by one of the black-clad men who called themselves Russian Orthodox activists. They pelted protesters with rotten eggs and ketchup, knocked men and women to the ground and called them demons and witches.

"They said they were doing God's will, and then they broke my nose," said Yasin.

Violence against activists has become so bad, he says, and police protection so meagre, that four months ago he and nearly 20 other activists started their own martial arts classes at a gym in southern Moscow where they meet three times a week.

PRODUCING CHILDREN

Putin says Russia does not discriminate against gays, but opponents say he has fostered prejudice with public remarks that seem to set them apart as second-class citizens.

When Putin was greeted by hundreds of rainbow flag-waving protesters on a trip to the Netherlands in April, he said the law would be no threat to the LGBT community, but suggested it could help reverse a decline in Russia's population, which fell to 141.9 million in 2011 from 148.6 million in 2001.

"It is imperative to protect the rights of sexual minorities, but let's agree that same-sex marriage does not produce children," Putin said.

Last month he said Moscow might seek changes in an agreement regulating adoptions of Russian children by French parents, as a French law allowing same-sex marriage went against "the ethical, legislative and moral norms of Russia".

Lawmakers say those morals are reflected in the proposed law against gay "propaganda", which could ban the promotion of gay events, including gay rights marches, and impose fines of up 500,000 roubles ($16,600) on organisers.

"The spread of gay propaganda among minors violates their rights," said Elena Mizulina, a pro-Putin deputy who chairs the lower house's family issues committee. "Russian society is more conservative, so the passing of this law is justified."

Russian psychologist Igor Kon wrote that in medieval times, Russian attitudes towards gays were more tolerant than those in western Europe, but that changed during the Soviet era, when Josef Stalin made sodomy punishable by up to five years in jail.

Homosexuals were then often persecuted and intimidated, and sometimes denied membership of, or expelled from, the ruling Communist Party when membership was key to promotion at work.

Homosexuality was decriminalised in 1993, two years after the Soviet Union broke up, but the stigma remains strong, and activists say the community is often blamed for chronic problems.

"The ultra-right radicals decide immigrants are responsible for unemployment, and then they decide that LGBT is guilty for the fall in the birthrate, that morals are in decline, that AIDS is spreading. All those problems can be dumped on the gays; it's convenient," said Yasin.

A survey by independent pollster Levada last year found that nearly 50 percent of Russians believe homosexuals should be given medical or psychological treatment, and 5 percent said they should be "destroyed".

Such attitudes mean life is fraught with danger for gays in Russia, opera singer Slava Kagan-Paley said.

"It's very hard ... I know a lot of young guys who cannot tell the truth to their parents," he said, speaking on a gay-friendly night at a central Moscow club.

"It ends up that they get thrown out of their house, and they end up on the street and end up actually being a prostitute because they have no money to live on."

GAY SCENE

LGBT Russians fear the propaganda law will bring a broader crackdown.

Gay rights campaigners say the bill that won preliminary parliamentary approval in January contains no details on what is considered propaganda, and fear the possible proximity of children could be used to apply it to any gay rights rally or even displays of affection.

Holding hands or kissing a same-sex partner in public, they say, might be enough to be hit with a $170 fine.

"The fact is that any demonstration of their sexual orientation is considered to be propaganda," said Yevgeny Arkhipovy of the Association of Russian Lawyers for Human Rights.

Some of the local laws against exposing minors to gay "propaganda" are packaged with bans on promoting paedophilia.

"While an adult can choose how to live and whom to involve in your intimate life, it is forbidden to impose on children preferences of a non-traditional nature that contradict (our) traditions," Sergei Zheleznyak, a United Russia lawmaker and vice-speaker of the State Duma, said last month.

In an interview with Interfax news agency on the Jan. 6 Russian Orthodox Christmas eve, Patriarch Kirill, the church's leader, equated homosexuality with drug addiction, prostitution and adultery as the biggest threats facing Russia.

"Society has always suffered blights, but in our time, as in the decline of the Roman Empire and other civilisations, they were considered as socially acceptable. And as a result the institution of the traditional family breaks down," he said. (Additional reporting by Sonia Elks and Ludmila Danilova, editing by Elizabeth Piper and Will Waterman)

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