BERLIN (AP) — German authorities said Friday they have concluded that a 2016 shooting in which a German-Iranian teenager killed nine people and then himself was prompted in part by the assailant’s right-wing extremist views.

Bavaria’s state criminal police office said it has now decided to classify the shooting in Munich as a “politically motivated crime.” It said that “the radical right-wing and racist views of the perpetrator should not be ignored.”

The announcement coincided with a new surge in concern about far-right violence in Germany, fueled by a botched attack on a synagogue in Halle this month in which a German using home-made weapons killed a passer-by and a man at a nearby kebab shop.

On July 22, 2016, the 18-year-old assailant targeted a Munich restaurant known as a hangout for youths of immigrant backgrounds. The dead included victims of Hungarian, Turkish, Greek, and Kosovo Albanian backgrounds.

The shooting took place on the fifth anniversary of the killing of 77 people by Norwegian right-wing extremist Anders Behring Breivik. Investigators have said previously the Munich shooter, identified as David Ali Somboly, researched that slaughter online. On Friday, they said that lengthy checks on various online platforms have turned up further evidence of far-right views.

They also said that revenge for bullying by schoolmates, some of immigrant origin, mental illness, a lack of social contacts and excessive playing of combat video games factored into the motives for the shooting.

Police stressed that their investigations have turned up no evidence that anyone else was aware of the shooter’s plans or incited him to carry them out, or that he was part of any network.

Last year, a man was sentenced to seven years in prison for selling a pistol and ammunition to the attacker. In a separate trial, a man who ran the web forum where illegal goods including the weapon were traded was sentenced to six years