A suicide bombing in Chechnya on Monday killed four people and injured three others in the latest violence in the Russian region which fought two wars with the Kremlin in 20 years.
Two officers and a soldier died in the explosion when their armoured vehicle travelling between the garrison town of Khankala and the capital Grozny made a stop, Vasily Panchenkov, a spokesman for the interior ministry troops said.
Three more servicemen received serious injuries and were admitted to hospital, he added.
Panchenkov said the blast was detonated by a bomber with a suicide belt. Body fragments believed to belong to the attacker were found at the scene, he said.
In a separate statement, the Chechen interior ministry said there were two suicide bombers.
The Kremlin fought two post-Soviet wars against separatist rebels in Chechnya and the violence has since spread into the nearby regions of Dagestan and Ingushetia.
Attacks on government officials and servicemen including those by suicide bombers are frequent in the North Caucasus.