The City Attorney’s Office has filed legal papers against a venue at the center of a tourist shooting Sunday, calling it an “illegal, overcrowded party for high school-aged youths.”

The “pre-litigation demand letter” was filed against Joseph Ursino, owner of the building at 414 Mason St., and Curtis Matthews, who rented out the party space, according to a statement from the City Attorney’s Office.

It alleges that the two face, “at a minimum, civil liability for violating the California Fire Code and for unlawful business practices.”

Such violations can be punishable by fines and penalties as well as disgorgement of all profits related to the unlawful conduct. The City Attorney’s Office is also evaluating the potential liability of event producer Labriette Collins.