Russia's Muslims divided over Syria air strikes
Russia's Muslim community has never been united, and Russia's air strikes in Syria are threatening to stoke existing tensions.
The air campaign began a week ago, with Moscow declaring it was targeting positions of so-called Islamic State (IS) and other Islamists.
But Turkey and other Nato allies fear the principal targets are Syrian opposition groups fighting President Bashar al-Assad.
Russia's Muslims tend to fall into three camps: those who support the Kremlin campaign, those who condemn President Assad and his allies but back actions against IS, and those who support IS.
More than 11 million Russians are Muslim, according to official figures that date back to 2011. But experts believe the true figure could be as high as 20 million - nearly 14% of the population.
Russia has more than 80 muftis who lead its Muslim community, but their influence and attitudes vary significantly.
Almost 6,400 of Russia's 7,000 mosques are controlled by muftis who are more or less loyal to state officials.
They supported President Vladimir Putin's decision to start air strikes on Syria - though in their statements pro-Kremlin muftis did not comment on Western allegations that many of the operations targeted moderate opposition groups.
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But some religious leaders in Russia do question Mr Putin's decision to strike.
"We don't know exactly where the bombs landed, so we can't be sure of anything," mufti Nafigulla Ashirov told the BBC. "However if Russian planes were targeting one of the sides of the civil conflict rather than IS positions - this can't be justified."
"IS is a force which came to Syria from abroad and people should resist it. However others shouldn't interfere in the civil war between pro-government troops and the opposition. This is an internal matter for the Syrian people.
"And this conflict should not be mixed up with resistance to IS," Mr Ashirov explains.
Most of Syria's opposition fighters are Sunni Muslims - like most of the Muslims who live in Russia.
Meanwhile, the forces supported by Moscow consist either of Alawites, who dominate the Syrian army, or Shias, who include Hezbollah forces from neighbouring Lebanon.
These are uncomfortable truths for some within the Russian Muslim community.
"Bashar al-Assad is well known for his actions against the Muslims of Syria," complains Muslim activist Ali Charinsky. "All Muslims are one community, one body - that is why we can't be happy about Russia's decision. None of my friends or the Muslims I know are happy about it."
But the idea of anyone openly protesting against Russia's action is highly unlikely, according to religious activist Ayrat Vakhitov, because of the fear of prosecution by the authorities.
He was himself arrested on several occasions by Russian security services in response to allegations of extremism.
However, the court ruled in his favour and the Russian security service, the FSB, even sent him an apology. Mr Vakhitov has since emigrated and supports the Syrian opposition while opposing IS.
According to the security services, nearly 2,500 Russians are currently fighting for IS and thousands more have gone to join IS from other former Soviet states.
But Mr Vakhitov insists few Russian Muslims support IS and their number is declining.
"Those whose friends or relatives have already joined IS support the radicals. They prefer to share their friends' positions," Mr Vakhitov explains.
"However, overall IS is losing support in Russia."
He believes the country's Muslims have begun to understand the reality of the Islamic State militant group. "The beautiful stories they tell are fake."