The two friends were standing at a bus stop on East 79th Street in the Grand Crossing neighborhood at the time of the beating.
The victim and his friend left a home around 3 a.m. and were waiting at the stop when a stranger approached and asked to use the cell phone. The request was denied, and the victim was attacked as his friend went for help.
The victim was hospitalized and pronounced dead a half hour later.
No one was in custody Monday.