CONTRA COSTA COUNTY (KCBS)— An ATM scam in Walnut Creek has police warning people to be aware of their surroundings especially when they’re withdrawing cash.

Ayanna Bastain, 32, a Pittsburg woman, was arrested for allegedly stealing Personal Identification Numbers from elderly people in a process police are calling, “shoulder surfing”. The woman went down during a sting operation at a Bank of America in Rossmoor, a community generally populated by the elderly.

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Walnut Creek Police Lt. Lanny Edwards said the woman was identified through photographs from thefts at other local banks. She allegedly had been engaged in shoulder surfing.

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Lt. Edwards described the crime as looking over the shoulder of someone using the ATM with hopes of seeing them enter their PIN. Edwards added when using an ATM to make sure you’ve properly ended the transaction.

“When you take your receipt, push the button that says you don’t want any more transactions. If they forget that, that gives the suspect the opportunity to follow them, type in their PIN and continue with additional transaction at the victim’s expense.”

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Meanwhile, Bastain has been booked at the county jail on suspicion of theft and elder abuse. She is being held on $270,000 bail.