A bomb has exploded in front of a school in the southern Italian city of Brindisi killing at least one girl and injuring six others, BBC News reported.

The blast went off as students were arriving at the Francesca Morvillo Falcone vocational school at around 07:45 (05:45 GMT).

Although no-one has said they planted the device, the city's mayor has blamed local mafia. At least one of the injured is in a serious condition.

Police are at the scene of the explosion and investigating the blast scene.

Reports say the explosive device had been placed in a rubbish container outside the school. It is unclear if one or two devices exploded, but one account suggests that the explosives had been in bags.

"Given the effect of the explosion, it appears that this was something quite powerful," an official from Italy's Civil Protection Authority said.

There is currently no concrete information as to who might be behind the attack and what the motive might be. But the mayor of Brindisi, Mimmo Consales, has blamed the local mafia network for what he calls "an unprecedented attack".