During opening statements of the racketeering trial of rapper Young Thug on Monday, prosecutors alleged that he co-founded and is the “proclaimed leader” of a criminal street gang known as “Young Slime Life” or “YSL” in Georgia.

The Atlanta-based rapper, whose real name is Jeffery Lamar Williams was indicted along with two dozen others last year, five of whom are expected to stand trial with him.

“The members and associates of YSL they moved like a pack with Jeffrey Williams as its head,” Fulton County Deputy District Attorney Adriane Love alleged during opening statements, according to ABC News.

In a trial set to last several months, prosecutors are expected to use Young Thug’s rap lyrics as evidence against him. There will also be testimony from other high-profile music industry figures.

The charges against Young Thug include violating Georgia’s anti-racketeering and gang laws, conspiring to violate the state’s Racketeer Influenced and Corrupt Organizations Act (RICO Act), participating in criminal street gang activity, violating the Georgia Controlled Substances Act, possession of a firearm while committing a felony, and possession of a machine gun.

He has pleaded not guilty to all charges.

According to prosecutors, the rapper founded YSL in 2012, describing it as a “criminal street gang” and claiming affiliation with the Bloods group, ABC News reports. The charges against the rapper stem from a sweeping indictment of a total of 28 individuals associated with YSL in 2022 on charges including murder, attempted murder, violent crimes, theft, and drug-related offenses.

In the past year, Young Thug’s legal team has filed several motions to have him released on bond, but all of them have been denied, and he has remained in custody since his arrest on May 9, 2022.