Nov 2, 2007, 15:13 GMT
Moscow - Russian investigators Friday suspected a lone student with a stuttering problem of planting a bomb which killed eight people and injured more than 50 travelling on a bus in the Russian city of Togliatti on the Volga River earlier this week.
The 21-year-old, who was killed in the blast, was suspected of having made the bomb and bringing it onto the bus, Russian media quoted investigators as saying.
The young man may have felt harassed because of his speech impairment and excluded from his social circle, sources said.
'He is the main suspect, but the motive is not quite clear,' an investigator told the Moscow-based daily Komersant on Friday.
'The suspect's personality is closely connected to the explosion,' said the head of Russia's Secret Service Nicolai Patrushev, according to Interfax news agency.
Shortly after the explosion aboard the bus, investigators had spoken of a terrorist attack and a possible suicide bomb blast.
Russian media said the man was a loner and had already tried to commit suicide on several occasions.
The explosion occurred in the centre of the industrial city about 800 kilometres south-east of Moscow as the bus was stopped at a traffic light. Many students and lecturers had boarded the bus to university at the time of the explosion.
The force of the explosion, which had the power of several hand grenades, also injured several pedestrians on the street.
About 42 of those injured including a number of children were treated in hospitals.
Security experts has expressed fear that the attack was a terrorist attempt to destabilize the country before parliamentary elections on December 2.
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