RIGA (Reuters) - A bomb exploded in front of a store in the centre of the Latvian capital Riga on Tuesday, injuring three bystanders, a police official said. A spokeswoman for the city‘s police said the bomb had exploded at a shop of the Baltic nation‘s largest fruit juice maker, Gutta, around 9:30 am (0630 GMT). „Two women injured by flying glass have been hospitalised, one in serious condition,“ Ieva Zvidre, a Riga police department spokeswoman, told Reuters adding that a third person had suffered minor injuries. Zvidre said the size of the device was yet not known and that no one had claimed responsibility for the blast. An investigation has been launched. „This is the first incident in Riga this year where people were injured when explosives were involved,“ she added. Though Riga is widely considered a safe city with little violent crime, there were 15 bomb blasts in the first half of 1999. Most of the explosions have been linked to turf battles among organised crime groups.