At least 15 people, including policemen and a priest, were killed and several others injured after unidentified gunmen opened fire at synagogues, churches, and a police post in Russia's North Caucasus region of Dagestan on Sunday, the region's governor said.
The simultaneous attacks occurred in Dagestan's largest city of Makhachkala and in the coastal city of Derbent with Governor Sergei Melikov calling it a "terrorist attack".
Officials said that the police personnel had killed four gunmen in Makhachkala and two in Derbent.
Melikov said that among the dead, in addition to the police officers, were several civilians, including an Orthodox priest who had worked in Derbent for more than 40 years.
"This evening in Derbent and Makhachkala unknown (attackers) made attempts to destabilise the situation in society," Melikov wrote on Telegram.
"We know who is behind these terrorist attacks and what objective they are pursuing," he added later, without specifying but referring to the Russia-Ukraine war.
"We must understand that war comes to our homes too. We felt it, but today we face it," he said.
Melikov said the "active phase" of operations in Derbent and Makhachkala had ended and that "six bandits have been liquidated".
The authorities will try to find "all the members of these sleeper cells who prepared (the attacks) and who were prepared, including abroad", he added.
He also said that June 24-26 have been declared days of mourning in Dagestan, with flags lowered to half-staff and all entertainment events cancelled.
Russia's Investigative Committee said it had opened criminal probes over "acts of terror" in Dagestan. There, however, was no immediate claim of responsibility for the attacks.
Russia's state media cited law enforcement as saying that among the attackers had been two sons of the head of central Dagestan's Sergokala district, who had been detained.
In Derbent, authorities were quoted as saying that both the synagogue and church were set on fire.
The incident comes three months after 145 people were killed in an attack claimed by the Islamic State on a concert hall near Moscow, Russia's worst terrorist attack in years.
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