Police are searching for clues after two people were killed and four others were injured when shots rang out in front of a northwest Baltimore store.

Police say that a lone gunman fired on people standing in front of the store at about 6 p.m. Wednesday. The suspect has not been found.

One man was pronounced dead at the scene and a second was pronounced dead at a hospital. Police say a third man was critically wounded, and a fourth man and two women had injuries that were not life-threatening.

Police say homicide detectives and an academy class are in the area Thursday combing for additional evidence, handing out flyers and knocking on doors.

Police have said they think the shooting was in retaliation for a homicide several days ago.