President Vladimir Putin said on October 20 Russia had foiled 20 militant attacks this year and was stepping up efforts to root out domestic terrorism, almost three weeks after launching air strikes against Islamist fighters in Syria.
The Russian authorities have arrested a number of suspected militants since the Syria campaign started on September 30, a development that stoked fears that militants could seek revenge by attacking targets inside Russia.
A week ago, Russia's FSB Federal Security Service said it had foiled a plot to attack Moscow's busy underground using explosives, news that rekindled painful memories among Russians of a series of deadly attacks on the metro in the 2000s.
Some of the men arrested in connection with the plot had undergone Islamic State training in Syria, the FSB said.
Speaking at a meeting in the Kremlin with military officers, Putin said the FSB had killed 112 militants and arrested more than 560 so far this year.
"The complex international situation demands that we strengthen our counter-terrorism work including inside our own country," said Putin.
"We need to act just as energetically and efficiently (as in the past). It is vital to expose the links between Russian militants with international terrorist groups and their sponsors."
Putin spoke as police said they had detained 20 suspects they accused of financing terrorism and advocating the creation of an Islamic caliphate on Russian soil.
The interior ministry said it had conducted a search of 24 addresses in the Moscow region where members of outlawed organization Hizbut Tahrir resided.
