SIOUX FALLS, S.D. (KELO) — A series of scam calls in Sioux Falls have stolen thousands of dollars from people. Banks and credit unions are urging customers to be cautious. "Do not give [information] out to someone over the telephone because we're not going to ask for those by calling you and asking for those. Financial institutions have a way to, again, verify your information," Levo Executive VP of Strategy and Service Preston Meline said. A series of fake calls cost people thousands of dollars starting Friday. "It said it was from either Sioux Falls Credit or Levo Federal Credit Union. The people talked to what turned out to be scammers," Sam Clemens with the Sioux Falls Police Department said. "They were able to elicit some information, and then later on they found out money was missing from their accounts." Remembering Joe Floyd, broadcasting and cable pioneer Anywhere from $1,000 to $11,000 was stolen. Levo Credit Union employees said they'll never ask for personal or account information over the phone. "We have security measures in place in which we verify if we're talking to the correct member that we have in front of us, or that we have on the telephone, but we will not ask for your private information," Meline said. Levo employees said they've seen everything from scam calls to text messages- even fake mail being sent to customers. That's why their staff offers additional information about scams and fraud. "Fraud is something that's escalating," Meline said. "More and more fraudsters are becoming more complex and sophisticated in their fraud efforts." Levo Credit Union is actively working with police following the recent scam calls.