Months of undercover work culminated in a full-scale police raid of four New Haven homes on Thursday, removing piles of contraband and arresting 11, according to a New Haven Police Department release.

Early Thursday morning, officers from the NHPD’s patrol division and SWAT team swept through a series of houses in the city’s Hill neighborhood to corral a group suspected of dealing drugs and committing robberies across town. Police teams recovered several types of drugs and firearms from the scene. Nine males and two females, believed to be associated with the “Slut Wave” gang, were subsequently arrested.

“Investigators recovered [a high-power assault weapon] as well as 21 ‘Exhibits’ for court,” an NHPD press release on the raid read. “Evidence found at the home included marijuana, cocaine, ‘crystal methamphetamine,’ a large amount of bottled ‘Codeine’, paraphernalia used for drug weighing, packaging and distribution, cash, at least 13 cell-phones and ammunition for a wide variety of guns including a loaded high-capacity magazine.”

NHPD spokesman David Hartman said that the arrests, which were announced in the department’s most recent CompStat meeting, resulted in over 30 pages of police reports. These reports detail the charges facing those arrested, which include illegal possession of an assault weapon, possession of a controlled substance with the intent to sell and risk of injury to a minor.

Thursday’s raid centered on the operation at 33 Button St., where police made five of the arrests. Officers arrived to find several men hiding in a bedroom, close to an Intratec Tec-9 machine gun.

“This high-power assault weapon is banned by name under CT general statute 53-202,” the NHPD release reads. “It may only be possessed by a special license. The transfer of such a weapon also requires a special registration. None of the three within the weapon’s reach possessed such a special license or permit.”

The gun in question was later found to be registered to a 61 year-old New Haven resident who had not reported it to be stolen.

Statute 53-202a bans assault-style weapons under the Conn. state law. It names more than 20 specific types of guns, and also sets forth other criteria such as bayonet mounts, telescoping stocks and threaded barrels in its definition of the term “assault weapon.”

Sam Hoover, a staff attorney at the Law Center to Prevent Gun Violence, said that Connecticut recently pushed for stricter regulation of access to assault weapons like the Tec-9.

Sociology professor Andrew Papachristos added that, though most street crimes are committed with handguns, larger weapons can be found and are capable of significant damage.

The release also shows that two children lived in the Button St. home at the time of the raid. Because of this, Tramaine Williams, 21, Raymond Melvin, 20, and Martese Allen, 18, received the “risk of injury to a minor” charge.

“The presence of a child does highlight how violence can affect the health not just of those involved in gangs or drug activities, but also the health of their families, children and communities,” Papachristos said.

Papachristos, who researches the prevalence of social networks in street gangs and interpersonal violence, added that the amount of contraband recovered demonstrates that the NHPD was diligent in identifying this group of traffickers.

Williams, who goes by the nickname “Mighty Midget,” was scheduled to fight in a Jan. 25 boxing match at Madison Square Garden in New York, but did not participate after being arrested.