A soldier in Russia's southern republic of Chechnya has shot dead three fellow servicemen before attempting to commit suicide, security officials say.
The soldier killed the commander of his platoon and two others before trying to shoot himself in the head, they added.
The incident took place on Sunday night at a military post near the village of Borzoi in southern Chechnya.
Separately, a Russian soldier was killed by an explosion while on patrol in central Chechnya on Sunday.
Russian forces have fought two major campaigns against separatist rebels in the predominantly Muslim republic since the collapse of the Soviet Union.
Last month, Russian President Dmitry Medvedev said life in Chechnya was returning to normal and that it might be time to end the security restrictions imposed there.