At least 19 people including police officials were killed after Islamic militants went on a rampage in Russia's Dagestan region. The gunmen targeted police posts, churches and a synagogue in coordinated assaults that took place in two cities of Derbent and Makhachkala.
Police had killed six gunmen involved in the attack. Among those killed, 15 were police personnel.
In the wake of the incident, Dagestan, a Muslim republic in southern Russia, has declared three days of mourning.
The coordinated attacks on Sunday had targeted cities on the Orthodox festival of Pentecost. An Orthodox priest, Nikolai Kotelnikov (66) was also killed in the attack.
This latest assault is one of the major attacks in Russia since March when 145 people lost their lives as gunmen opened fire at a concert in Moscow.
Though no one has claimed responsibility for the Sunday attacks, reportedly, the Islamic State group is believed to be behind the act. The Moscow concert attack was claimed by the Islamic State group days after the incident.
The video footage posted on social media showed people wearing dark clothes shooting at police cars. In Derbent, gunmen set Kele-Numaz synagogue and a church on fire.
Though assailants were not formally identified, Russian media reports said that the gunmen included two sons of Magomed Omarov, the head of the main Kremlin party United Russia's regional branch in Dagestan. Omarov has been detained by the police for questioning.
Meanwhile, in a video statement, Dagestan Gov. Sergei Melikov accused Ukraine of involvement in the attacks. "We understand who is behind the organisation of the terrorist attacks and what goal they pursued," he said.
Kremlin spokesperson Dmitry Peskov said Russia's President Vladimir Putin offered his condolences to those who lost their loved ones and offered all efforts to help the victims.
The Investigative Committee, the country's state criminal investigation agency, said all five attackers were killed.
