At a hip-hop festival called Craze Fest in Hammond, Indiana, just outside of Chicago, rapper Chief Keef appeared on stage as a hologram. But his Saturday night performance only lasted one song before the police shut it down.

Chief Keef, born Keith Cozart, originally planned to hold a benefit concert for his friend and a toddler who were both killed during a shooting this month. The concert was to be held at a theater in Chicago, but Mayor Rahm Emmanuel's office reportedly pressured the theater to cancel the event, according to the Chicago Tribune. The New York Times reported the mayor's office called Chief Keef "an unacceptable role model" whose music "promotes violence."

Instead, Chief Keef told his fans that he would perform at an undisclosed location and enlisted Hologram USA to help him appear virtually rather than physically, citing outstanding warrants for his arrest in Illinois. Fans weren't told Chief Keef would be performing in Hammond at Wolf Lake Pavilion as part of Craze Fest until 9pm that night.

According to the Chicago Tribune, Chief Keef performed his hit "I Don't Like" from a sound studio in Beverly Hills, California. "[He] was talking about putting a stop to violence when the power was cut off. Police rushed toward the stage, turning the music off about 10:25pm. Shining flashlights, they ordered concertgoers to leave. Fans who gathered Saturday left the grounds in an orderly fashion, though disappointed."

Hammond Mayor Thomas M. McDermott told The New York Times that all of the performances at Craze Fest had been vetted by officials because the event was held in a public park. “I know nothing about Chief Keef,” Mayor McDermott told the Times. “All I’d heard was he has a lot of songs about gangs and shooting people—a history that’s anti-cop, pro-gang, and pro-drug use. He’s been basically outlawed in Chicago, and we’re not going to let you circumvent Mayor Emanuel by going next door.”

Hologram USA CEO Alki David condemned the mayor's actions in a statement. "Shame on the mayor and police chief of Hammond for shutting down a voice that can create positive change in a community in desperate need.... This was a legal event and there was no justification to shut it down besides your glaring disregard for the first amendment right to free speech. Mark my words if you censor us you only make us stronger."

Hologram USA has had a litigious couple of years. Last year, it asked for a permanent injunction to keep a Billboard-sponsored performance from using a hologram of Michael Jackson. Although a judge denied the request, the company argued that it has patented technology based on the Pepper's Ghost illusion that paved the way for a performance by "Tupac" in 2012.

Update: Owen Phillips, who works with Hologram USA, e-mailed Ars to add that "every ruling since" the Michael Jackson "hologram" performance has been in favor of Hologram USA's ownership of its patent. "Fox settled with HUSA over the Homer Simpson hologram and other organizations are honoring it," Phillips wrote.

Correction: This story originally identified Craze Fest as being in Illinois, it actually took place in Indiana.