The latest incident happened between 6 a.m. and 6:30 a.m. May 29 in the 2400-block of West Montrose Avenue.
Authorities said two male suspects approached the victims as they walked alone.
They then beat or choke the victims and took their belongings.
In two incidents, the victims were kids on their way to school.
Both suspects are described as men between 17 and 20 years old and about 6-feet tall.