Seven alleged members of the MS-13 gang are charged in the brutal stabbing death of a 21-year-old man in Maryland this summer — and six of them are in the US illegally, federal immigration officials said Sunday, according to a report.

The suspects, including a 16-year-old, were charged with killing Daniel Alejandro Alvarado Cuellar, whose body was found July 31 in a grassy area outside his apartment building with “multiple sharp-force injuries,” Fox News reported.

A motive for the attack is still under investigation, police said.

“We know this group of individuals was conducting surveillance on (Cuellar), they were watching him, following him,” Baltimore County Police Officer Jennifer Peach told Fox. “We know they used knives and multiple people stabbed him multiple times.”

All seven suspects are charged with first-degree murder.

The alleged attackers are identified as Hugo Portillo-Chavez, 31; Jonathan Escobar-Hernandez, Marlon Leonardo-Flores and Odaliz Rosa-Yanez, all 20; Jose Fausto Rivera-Coreas, 19; Edwin Edgardo Garcia-Martir, 18; and 16-year-old Alexander Velasquez-Hernandez, who is charged as an adult.

Immigration and Customs Enforcement officials did not specify which six are in the country illegally, but said five are from El Salvador and one is from Mexico.

The six were identified as members of the notorious MS-13 through an ICE database.

Police believe Cuellar’s slaying was part of a war between two rival street gangs.