Two blasts hit southern Russian republic
Police in the Kazbekovsky region say the bus blast could have been caused by the careless handling of explosives.
The minibus exploded on a motorway not far from a police station.
Earlier reports suggested the woman may have been wearing a suicide belt.
The driver of the bus, Abulakhmid Khamilov, said the bus began filling with smoke before the bomb went off in the left side of the back of the bus.
“People panicked with some passengers jumping out while the vehicle was still moving,” he said.
Three people were treated in hospital, one of them for serious injuries.
According to witnesses, a woman under the age of 30 may have been carrying the explosives. She was blown to pieces.
Investigators believe she either detonated them herself or mishandled the explosives, triggering the blast.
Dagestani police representative Sapyula Salatgireev confirmed that the woman was sitting at the back of the bus.
“We're working to determine the type of the explosives and doing everything possible,” he said.
A taxi driver and a woman passenger were injured in a major blast hours later in Makhachkala. They were driving along when an explosive device equivalent to 8 kilos of TNT detonated in a rubbish bin.
Three young men were detained by police after they tried to flee the scene of the blast.
The intended target of the attack is not yet known.