Russia is conducting an “anti-terrorist operation” in the southern region of Dagestan. By Sunday morning, three people were detained, the National Anti-Terrorist Committee reported, citing Russian press agencies, Reuters reports.

Russia has been on high alert since the March 22 gun attack on a Moscow concert hall, the country’s worst in 20 years, which killed at least 144 people.

“The security services detained three bandits who were planning a series of terrorist crimes. During the inspection of the places where the perpetrators were detained, automatic weapons, ammunition and a ready-to-use improvised explosive device were found,” the Committee noted.

Earlier, the committee said that the alleged criminals were blocked by special services in several apartments in the residential areas of the capital of the Makhachikala region and one of the largest cities of the republic – Kaspiysk.

There are no victims among the civilian population and law enforcement officers. The “operation” is ongoing, the committee reported.