Russia`s Medvedev Urges Vigilance After Bomb Blast

Security officials said they suspected a female suicide bomber was behind the blast on Thursday in Vladikavkaz.

Russia faces a lingering terrorist threat and cannot drop its guard, President Dmitry Medvedev said on Friday, a day after a suspected suicide bombing killed 12 people.

Security officials said they suspected a woman had blown herself up in Thursday's blast at a bus stop in Vladikavkaz, a city in Russia's North Caucasus region where Moscow has been struggling to contain a wave of violence.

"This event shows that the terrorist threat in our country remains. It is no time to relax," Medvedev said at a meeting with senior law enforcement officials in St Petersburg.

"Even though active terrorist attacks in our country have been suppressed, the conditions for these kinds of crime exist."

Alexei Malashenko, a security analyst at the Moscow Carnegie Center, said the use of a female suicide bomber could point to militant Islamists who have not used the tactic on this scale since a spate of deadly attacks that culminated in the 2004 Beslan school siege, in which more than 300 people were killed.

In a separate explosion on Friday in Ingushetia, also part of the North Caucasus region, a police officer with the organised crime unit died after a bomb went off under his car as he opened the door, Interfax news agency reported.

After a decade of fighting, Russia has largely quelled a separatist insurgency in Chechnya, once the biggest flashpoint in the North Caucasus, but explosions, gunfights and ambushes are frequent in other parts of the region.

Officials on Thursday had said 11 people were killed in the Vladikavkaz bombing but they later revised the figure to 12.

Female suicide bombers have attacked civilian and military targets in Iraq after the U.S. invasion in 2003. They are difficult to defend against because women attract less attention and are problematic to search, security experts say.

Women with explosives strapped to their bodies have carried out attacks in Russia that included a hostage-taking at a theatre in Moscow, the blowing-up of passenger aircraft, and the Beslan siege.

Beslan is in the same North Ossetia region where Thursday's bus stop explosion took place.

Russia's chief investigator Alexander Bastrykin said the blast may have been linked to a sectarian conflict between mainly Christian North Ossetia and the neighbouring Muslim region of Ingushetia.