A car bomb killed three police officers and injured four others Monday, Sept 16, in an attack on a local Interior Ministry branch in Russia’s North Caucasus republic of Chechnya on Monday, the ministry said.

The attacker drove a Russian Lada at high speed toward the main gates of an Interior Ministry compound. After an on-duty officer raised a protective barrier in the road, the bomber blew up the car, the ministry said in a statement, according to RIA Novosti.

The bomb had an explosive force equivalent to about 60 kilograms of TNT, the investigative committee cited experts as saying, and left a three-meter-wide crater in the road.

In a separate incident, police detained a man wearing a suicide vest and carrying a gun at a police station in Russia’s North Caucasus republic of Ingushetia on Monday morning, a regional police representative told RIA Novosti.

The spokesman added that the man has been identified, detained and disarmed, but did not give further details as to his identity.

The two neighboring districts have the same name but are considered separate parts of their respective regions.

Attacks on security forces, police and civilians occur regularly in the North Caucasus, generated by ethnic, religious and political rivalries, as well as poverty and corruption. The violence is also fed by an Islamist insurgency, which has been especially resilient in Dagestan and fueled a series of bloody post-Soviet wars in the neighboring republic of Chechnya.