Gunmen attacks churches, a synagogue, and a police post in Dagestan’s North Caucasus region, according to Russian authorities. The assaults resulted in the deaths of at least 15 police and National Guard officers, several civilians, and an Orthodox priest.

The incidents occurred in Derbent and Makhachkala on Pentecost Sunday for the Russian Orthodox Church, leaving 12 others injured.

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Videos shared on social media and Russian television depicted smoke and flames over Derbent, a predominantly Muslim area with an ancient Jewish community, following an attack on a synagogue. In Makhachkala, the capital, armed assaults targeted churches and a police checkpoint.

Russia’s Investigative Committee initiated terrorism investigations in Dagestan, bordering Chechnya and known for its economic challenges. An archpriest and two police officers were among those killed in the attacks.

Authorities reported that six attackers were “neutralized,” although their identities remain unknown. The incidents come after 133 people were killed in an attack on a Moscow concert hall, claimed by ISIS-K, and amid previous unrest in Dagestan, including protests at an airport last year.

The violence, targeting religious sites and civilian infrastructure, marks a significant escalation in the region’s recent history of sporadic conflict.