crocus
© Sputnik / Sergey Bobylev
Iran alerted Russia of a looming major "terrorist operation" in the country days before the deadly Crocus City Hall attack, which claimed the lives of over 140, Reuters reported on Monday, citing three sources familiar with the matter. Kremlin spokesman Dmitry Peskov, however, told reporters he was not aware of such a warning.

The Iranian side reportedly attributed the imminent attack to terrorists within Islamic State's Afghanistan-based ISIS-Khorasan (ISIS-K), citing information obtained during interrogations of suspects in recent deadly bombings in the country. Earlier this year, Tehran detained some 35 suspected members of ISIS-K, following a major blast in the city of Kerman that killed about 100 people.

"[ISIS-K members] were instructed to prepare for a significant operation in Russia... One of the terrorists said some members of the group had already traveled to Russia," one of the sources told the news agency.

Reached for comment, the Kremlin spokesman Dmitry Peskov said he was not aware about any warnings coming from Iran ahead of the attack. "I do not know anything about this," he told reporters.

The Afghanistan-based offshoot of the terrorist group has claimed responsibility for the massacre shortly after the attack. The US and the EU have insisted that ISIS-K was the sole culprit behind the Crocus City Hall attack.

Moscow, however, appears to be skeptical about the ISIS-K narrative, with top officials signaling that preliminary findings indicated Ukraine -and other parties- might have been involved. President Vladimir Putin said that the attack was carried out by "radical Islamists" but that its true mastermind is yet to be established. The head of Russia's Federal Security Service (FSB), Aleksandr Bortnikov, suggested that the US, UK, and Ukraine may all be linked to the massacre.

On Monday, the Russian Investigative Committee announced it has launched a probe into allegations that Ukraine and its Western backers, including the US, are involved in terrorist activities on the country's soil. The agency is now investigating the "organization, financing and conduct of terrorist acts" by those nations, after a group of MPs filed a complaint on the matter.