A Massachusetts man said he fell victim to a scammer while trying to withdraw money from an ATM around the same time a similar thing happened to a woman in Boston late last week. The man, named Don, said he was at the remote Bank of America ATM on Bussey Street in Dedham, which is located in the parking lot of the CVS Pharmacy in Della Park Plaza, when he had trouble with his transaction Friday afternoon. “I think it might have been because my bank card got stuck, and he came over and offered to help,” Don said. That man, who Don thought was a Good Samaritan, turned out to be a scammer who swapped Don's debit card for a random card. According to Don, the scammer used his debit card to make three separate withdrawals and cash checks at bank branches. Don said he lost a total of $12,000 to the scam. “I guess you have to be very, very vigilant, and of course I thought I was,” Don said. Don's case is strikingly similar to what happened to Megan Bates at a Bank of America ATM in East Boston. Bates said she was withdrawing cash to pay for her lunch Friday afternoon when a man claimed there was something wrong with the ATM and her transaction had not completed. The man took Bates' debit card under the guise of helping her and swapped it for another card. The scammer in this case made three separate withdrawals at Bank of America banks in Boston, and Bates lost a total of $12,000. “I fell for it. I don't know why I fell for it,” Bates said. “I never understood what was going on, and I guess she didn't understand either,” Don said. Robert Siciliano, an identity theft and cybersecurity expert, said these crimes are a popular form of ATM skimming, where thieves only need a person's debit card and PIN. “There's no doubt about it, this is part of an organized crime ring,” Siciliano said. As for the checks cashed with Don's card, Siciliano said they were stolen checks made out to a person with Don's name. “Could have been from anyone,” Siciliano said. Bates had her stolen funds refunded by Bank of America, and Don hopes the bank does the same for him. Dedham Police Chief Michael d'Entremont said they are investigating what happened to Don, but it's unclear if the two incidents are related.