AREZZO, Italy — A police officer was convicted of manslaughter and sentenced to six years in prison today for the death of a soccer fan that caused riots across Italy in 2007.

Prosecutors had asked the jury to convict Luigi Spaccarotella of murder and the manslaughter verdict brought cries of "shame, shame" from family and friends of the victim.

Gabriele Sandri, a 26-year-old disc jockey from Rome and a Lazio fan, died in November 2007 after being hit in the neck by a bullet while sitting in a car at a highway rest stop.

Defense lawyers argued Spaccarotella had fired shots to disperse a scuffle between two groups of rival fans, while prosecutors maintained he had purposely aimed at the car when the clash was over.

As news of the death spread, soccer fans in Rome, Milan and other cities rioted, smashing windows, hurling stones at officers and attacking a police barracks near the capital's stadium.

Tuesday's verdict could set the stage for more violence. Sandri's friends were ejected from the courtroom for voicing their anger and continued to protest outside the building.

Sandri's mother fainted after the verdict and required an ambulance. His father Giorgio called the ruling "shameful" and said the family would appeal. Speaking to Italy's Sky TV news channel, he also urged fans to "stay cool" and not protest violently.