WAUKEGAN (CBS) – Waukegan police credit a quick-thinking officer with helping solve a recent string of armed robberies, two of them at ATMs.

A Waukegan patrol officer conducted a traffic stop Saturday night when he observed what appeared to be a handgun, two masks and a purse inside the vehicle. The purse belonged to a victim who had been robbed earlier in the week, Waukegan police said in a news release Monday.

The three occupants of the car were taken to the police station and implicated themselves in three armed robberies, including two robberies that occurred at ATMs in the community. Police had issued a warning to the public last week.

Charged with aggravated armed robbery were Orlando Salazar, 19; Steve Briggins, 17, and Juan Martinez, 19, all of Waukegan. All were being held at the Lake County Jail on $200,000 bond each. A 15-year-old was charged and taken to a juvenile detention center, police said.

The gun inside the car turned out to be a BB gun, police said.

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