The number of casualties from the terrorist attack on a concert hall in Moscow’s “Crocus” city has increased to 143, with over 551 people wounded.

The Russian Investigative Committee announced today that intelligence agencies have arrested four individuals about the terrorist attack in the “Bryansk” region.

Near the Ukraine border, intelligence agencies carried out the arrests, as indicated.

According to Alexander Bortnikov, director of the Federal Security Service, the ongoing arrest operation has successfully captured 11 individuals, including the four terrorists behind the attack.

Recall that the attack has been attributed to the terrorist group ISIS.