And the IRS (or your country's equivalent) will never call you on the phone and demand that you pay your back taxes with gift cards. The police will not be on your doorstep to arrest you in two hours. Nor will an agent from the CIA, FBI, NSA, NCIS, AFT, DHS, or any other government alphabet agency. DH used to work for one of the alphabet agencies, so when the "IRS" called and demanded $5000 or a [government agent*] would be arresting me, I said "There's a [government agent] sitting across the room from me. He can do it and save someone else the trip." Scammer hung up in microseconds.
*DH has asked that I don't identify his agency.