By CBSLA Staff

LOS ANGELES (CBSLA) — A man and his father have been accused of robbing 18 Trader Joe’s stores located in Los Angeles, Ventura, Orange, San Bernardino and Riverside Counties between August and December of this year.

Gregory Johnson and his son, Gregory Eric Johnson, were arrested Dec. 4 after allegedly robbing a Chino Hills Trader Joe’s, according to a criminal complaint released Thursday.

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According to the complaint, a witness who had been hired by the store spotted the elder Johnson leaving the location following reports of a robbery wearing clothing consistent with the description given by workers. The elder Johnson allegedly got into a vehicle being driven by his son.

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When police stopped the vehicle, they found a loaded black semi-automatic handgun, a blue drawstring bag with more than $3,800 inside and a blue hooded sweatshirt that workers identified as belonging to the robbery suspect, according to the complaint.

The two are also suspected of robbing 17 other Trader Joe’s locations, resulting in a loss of approximately $57,000. According to the complaint, the pair hit locations in Brea and Ranchos Palos Verdes twice. They are also accused of an attempted robbery at an 18th location.

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According to the Federal Bureau of Investigation, the robberies almost always happened just after opening or just before closing, though it was not immediately clear how both men were allegedly involved in each of the robberies.