The UN-designated terrorist organization Islamic State claimed responsibility for killing a Russian policemen in a series of bombings in a Russian region of the Caucasus Mountains, according to a statement circulated on social media on Wednesday.
Three landmines in the southern Russian region of Dagestan exploded under a police convoy on Tuesday evening, killing one officer and wounding two others, state news agency TASS reported.
A law enforcement source told TASS that the local gang from the Novy Khushet suburb of Dagestan's capital, Makhachkala, were suspected of involvement in the bombings.
The source said police were confirming whether the so-called Khushet gang had sworn allegiance to Islamic State.
Meanwhile, about 20 suspected Islamic State militants were detained in Moscow, state news agency RIA Novosti reported Wednesday.
Earlier this month, authorities in Dagestan detained several Islamic State militants who were preparing a terrorist attack and revealed information about an abandoned house where they were keeping about a tonne of explosives, the Interfax news agency reported.
For decades, Russia has struggled with a homegrown Islamist insurgency in the Caucasus Mountain regions of Dagestan, Chechnya and Ingushetia.
However, that insurgency has quieted down in recent years as many of the militants went to Syria to join Islamic State and other extremist groups, according to a report released this month by the International Crisis Group, an anti-war organization.
During Russia's military operation in Syria, it eliminated more than 2,000 rebels who had come to Syria from Russia, including 17 rebel field commanders, Russia's Defence Minister Sergei Shoigu said earlier this month.