Costco shoppers, beware!

A man who was filling his car with gas at a Chicago-area Costco was the victim of a carjacking incident on Wednesday. He was injured during the incident.

The man was adding fuel to a Mercedes-Benz sedan in broad daylight when a man in a ski mask and black clothing walked toward the vehicle, sat in the driver’s seat, started the car and drove away.

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Desperate to stop the thievery, the man who owned the vehicle tried to jump in through the passenger side door. He then fell, injured his leg and was taken to Glenbrook Hospital for treatment.

Neither the criminal nor the car have been located. The incident prompted local police to issue a warning on social media.

“HIDE your belongings. LOCK your car. TAKE your keys (FOBS),” the post says. “PLEASE, Lock your car and REMOVE keyfobs from your parked cars.”

Last month, a woman named Niketa Patel was carjacked while filling up her tank at a different Chicago-area Costco.

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“I just saw that somebody jumped in my car,” she told local outlet NBC 5. “He has a ski mask on. So, I was holding the driver’s side door, and I was waving my head, don’t do it. But that guy, he wasn’t scared.”

It’s not clear if the two situations are connected, but the Costco where Patel’s car was stolen was the scene of three car thefts and two attempted carjackings between July and September.