The robbers appear to target victims with cellphones, especially people sitting in their car talking on the phone. The suspects are believed to be drive around areas of Oakland looking for prime targets, according to police.
The first suspect is described as an 18- to 21-year old black man standing about 5 feet 10 inches tall and weighing about 230 pounds with a short black afro and brown eyes. He has been spotted wearing a white shirt, baggy jeans and was armed with a silver revolver.
A second 18- to 21-year old suspect is described as a black man standing about 5 feet 10 inches tall who weighs 180 pounds and was seen wearing a black ski mask, black hoodie, black gloves, baggy pants and was armed with a black semi-automatic pistol.
Another 18- to 21-year-old black man wearing a ski mask, a black hoodie, black gloves and baggy pants is a suspect in the cellphone incidents. He has not been seen armed.
A final suspect, a 15-year-old black boy who weighs 145 pounds and is about 5 feet 6 inches tall, was last seen in a dark navy blue hoodie and was not armed.
Police said the robberies have occurred in the 900 block of Ninth Street, the 900 block of 18th Street, the 6500 block of Lucas Avenue and the 800 block of Brooklyn Avenue.
Police advise cellphone users keep the device and other valuables in a pocket and concealed.
