A Russian man suspected to join the Islamic State group has been detained at Moscow’s Vnukovo airport. The Siberian resident was detained by Russia’s Federal Security Service while he was allegedly trying to fly to Turkey to cross into Syria.

The criminal case has been referred to the district military court while the suspect has been taken into custody. The man, if proven guilty, is likely to face a fine up to $7,500 and up to 10 years of imprisonment as he was allegedly planning to take part in the activities of an organization recognized as terrorist in the country.

Elena Sutormina, the chairperson of Russian Civic Chamber’s commission on developing public diplomacy and supporting compatriots abroad, said last week that around 2,500 Russians and 7,000 nationals from other Commonwealth of Independent States were fighting for ISIS militants in the Middle East.

According to Russia's Tass news agency, Marina Kochubey, the chairperson of the Scientific Advisory Board at the Anti-Terrorist Center of CIS Member Countries, also announced similar figures earlier. Kochubey said, according to 2014 data, up to 1,500 Russian nationals were involved with ISIS forces in Syria and Iraq.

Meanwhile, the Russian President Vladimir Putin is preparing to launch airstrikes against ISIS militants in Syria if the United States rejects Russia’s proposal to join forces. Putin wants U.S.-led coalition officials to coordinate their campaign with Syria, Iran and Russia.

“Russia is hoping common sense will prevail and Obama takes Putin’s outstretched hand,” Bloomberg quoted Elena Suponina, the senior Middle East analyst at the Institute of Strategic Studies which advises the Kremlin, as saying. “But Putin will act anyway if this doesn’t happen."

Russia has been recently getting more involved in Middle Eastern issues. Israeli Prime Minister Benjamin Netanyahu and Turkish President Recep Tayyip Erdogan travelled to Russia Monday and Tuesday, respectively, to hold talks with the Russian President.