MAKHACHKALA, Russia, Oct 23 (Reuters) One woman was killed and five passengers were hurt in a blast in a minibus in Russia's southern region of Dagestan, scene of frequent insurgent attacks, police said.
Police initially said the woman victim was carrying a suicide-belt and had deliberately triggered the blast, but an official later said it was possible the explosives she was carrying went off accidentally.
The minibus, travelling from the Dagestani town of Khasavyurt to a nearby village, exploded around 100 metres (yards) from a police post.
Three of the five wounded people were rushed to hospital with severe injuries, police said.
''We are investigating the possibility that it was a suicide-belt but that is not the main line of inquiry,'' said a local law enforcement official, who did not want to be identified.
The official said initial forensic examination suggested the woman had been carrying components for an explosive device, but not a ready-made bomb.
Russia's Itar-Tass news agency quoted a local prosecutor as saying: ''It seems most likely that the blast happened accidentally, so it would be extremely hard to say she was a suicide-bomber.'' Dagestan is next to the Chechnya region, where Russian forces have been fighting a long-running campaign against separatist insurgents.
Chechnya is now broadly calm, but the violence has spilled over into neighbouring regions including Dagestan and Ingushetia. Bomb blasts and gunfights between police and insurgents are regular occurrences.
Analysts say the violence in Dagestan is caused by a combination of Islamist insurgents, organised criminals and feuds between local clans.
REUTERS SZ KP1724