A Russian teenager has been killed and 11 others injured after a student brought a grenade to school and it accidentally exploded.
The boy who brought the grenade has since been detained by police.
He had found it on the street and brought it to the computer club on Monday (local time), showing it to a friend, a spokesperson for the local Dagestan government told media.
It exploded after the friend accidentally pulled out the safety pin.
Three of the injured students are in intensive care, a hospital spokesperson said.