Four suspects have been arrested and 25 alleged perpetrators identified, following armed confrontations between Syrian and Chechen youths in Vienna in July, police have announced.

A nine-millimetre pistol was seized during the raids, Gerhard Winkler, head of the investigation department at the State Criminal Police Office, told a press conference on Thursday evening. “It is certain that at least six shots were fired,” he said.

Along with the firearm, a gas pistol, six knives, seven mobile phones, two pepper sprays, four computers, and a car were also seized. The nine-millimetre weapon is believed to have been used in the clash that took place in Anton-Kummerer Park in Vienna’s 20th district, Brigittenau, on the night of 6 July.

Speaking at the same press conference, Interior Minister Gerhard Karner said the arrests mean that all the ringleaders had now been tracked down.

The four arrested individuals are believed to include a Syrian, two Russians of Chechen descent, and an Austrian. These follow previous arrests of two Syrians, a Chechen, and a Croatian with Turkish roots.

The clashes occurred across several districts in Vienna. However, both Syrian and Chechen communities later stated that the violence was not ethnically motivated, and a peace treaty was signed.