Four Oakland, CA, police officers involved in a sexual misconduct scandal will be fired, and seven more suspended without pay, for violations that include attempted sexual assault and assisting in the crime of prostitution, city leaders said Wednesday.

In all 12 officers (including one who is ordered to receive counseling and more training) are being disciplined, officials said, making it one of the largest mass discipline cases in the department’s recent history.

The recommended discipline was handed down Wednesday at the conclusion of the city’s sweeping administrative investigation into allegations of officers having sex with an exploited teenager who goes by the name Celeste Guap, or knowing about officers’ encounters with Guap, who is the daughter of an Oakland police dispatcher, the East Bay Times reports.

“The discipline we have announced today sends a loud and clear message that we will hold our officers to nothing but the highest standards of professionalism and integrity,” Mayor Libby Schaaf said during a hastily called news conference. “The people of Oakland and the decent men and women of the Oakland Police Department deserve no less.”