A 33-year-old suspect in the 2012 attack on visitors and officials at Germany’s Kunsthaus Erfurt confessed to have brutally beaten curator Dirk Teschner, the dpa reports. The unnamed man admitted his guilt at the start of a trial in which he and six others are accused of assault, incitement of violence, and using symbols of unconstitutional organizations.

He admitted to having punched and kicked Teschner during the attack on July 13, 2012 that left Teschner with a broken nose. The seven men were reportedly part of an extreme-right organization in the region. Two did not enter a plea as the trial began. Four others pleaded not guilty.

Kunsthaus Erfurt director Monique Förster had a beer bottle broken over her head. Others were also reportedly hit by full bottles being thrown by the alleged assailants. Another woman was thrown into the hood of a car while fleeing the scene with her child.

The attack occurred during the opening of Miss Painting, which featured the work of Katja Brinkmann, Franziska Holstein, Kristina Schuldt, and Anne Vorbeck.