A star witness took the stand Monday as the third week got underway in the Lesandro "Junior" Guzman-Feliz murder trial.

Kevin Alvarez broke down in tears while admitting to his role in dragging the teen known as Junior out of a Belmont bodega last year.

Alvarez, who was charged with second-degree murder in the case, said, "I punched him in the face with a closed fist a few times." He told the jury that he kicked Junior while he was down before dragging him out to the street, where prosecutors say he was stabbed to death by other gang members.

Five men are charged with first-degree murder in the case.

Alvarez identified each of the suspected killers in court. He said the gang was ordered to hunt down members of Sunset, a rival faction within their Trinitarios gang, on the night of Junior's death last June.

Alvarez testified that Los Sures and Bad Boys, two other Trinitarios chapters, stumbled upon a frightened Junior in Sunset territory and approached him with questions.

"The only thing I heard him say is that he wasn't Sunset," Alvarez testified.

Alvarez, who used his mother's Acura as a getaway car, says Junior screamed "stop" and "help" as he was hit with knives and a machete by all of the five defendants at the same time. He says he backed away because he was scared.

Alvarez's testimony will continue Tuesday.