MOSCOW (Reuters) - Law enforcement officers killed five suspected militants on Tuesday in the North Caucasus, Interfax reported, near Russia's most popular ski resort where three Moscow tourists were gunned down last week. "It is possible that these are the bandits who shot the tourists," an unnamed security source told the news agency. Rebels fighting for a Muslim state separate from Russia have claimed responsibility for the tourists' deaths. Fighters have said they also ordered a suicide bombing that killed 36 people last month at Moscow's Domodedovo airport, the busiest in Russia. President Dmitry Medvedev warned earlier on Tuesday that unrest in the Arab world could affect Russia and spur more extremism. Russia is home to some 20 million Muslims, or a seventh of the population.