 Credit card skimmers have been found at Big Y supermarkets in Plainville and in Naugatuck. The devices steal credit card information of customers and are attached to self-pay stations by crooks. Big Y says the company is working with law enforcement to determine who's responsible. If they develop information that a customer's information has been compromised, they will work to help them to protect themselves. But they are asking anyone who has shopped at those supermarkets to use credit cards to check their statements.