Brussels  - European Commission President Jose Manuel Barroso on Wednesday described the shooting spree in a school in south-west Germany that has left at least 15 people dead as a "senseless" act of violence.

"We are appalled and saddened by the senseless violence that cut short so many lives and injured and traumatised many others," the head of the European Union's executive arm said in a statement.

"On my own behalf and that of the European Commission I offer my deepest condolences to the families and friends of the victims of the school-killing of Winnenden," Barroso said.

A 17-year-old former pupil shot dead nine students and three female teachers at the school in Winnenden, near Stuttgart, in one of the worst incidents of its kind in Germany. He also murdered three others outside the school before being killed by the police.

The shooting in Germany happened just hours after at least 11 people were killed in a similar shooting spree in the US state of Alabama on Tuesday. (dpa)