Say what you will about Washington politics, but older Americans generally still trust many of the federal government’s agencies and operations. Unfortunately, crooks know this. The AARP Fraud Watch Network has been inundated with calls this year about scams involving someone impersonating an IRS agent, Medicare official, Social Security Administration officer, FBI agent or other government worker. Here are some of the impostor frauds we’ve heard about.

1. Medicare malice

A 90-year-old Maine resident received a call from someone claiming to be a Medicare official. The impostor said that Medicare was sending out new plastic cards to protect beneficiaries from the spread of COVID-19. The caller needed to confirm his Medicare number to make sure the card was accurate. He gave his Medicare number to the scammer but reported the incident to Medicare in time to stop any rip-offs.

2. Grants grift

A “friend” on Facebook told a 69-year-old Riverside, California, woman that she had received a large federal grant. The woman was eventually talked into sending $65,000 for a promised $180,000 federal grant that never came. Turns out that the Facebook friend’s account was hacked and the contact had come from a scammer.

3. Social Security scam

An 85-year-old Maryland woman got a call from someone pretending to be a federal agent who said her Social Security number had been stolen and used to rent a car that was involved in a violent crime. This incident had compromised both her Social Security and bank accounts, she was told, and both were to be “suspended.” To keep access to money she needed to pay her bills, she was told to go to a local store and convert her cash in the bank to Bitcoin, then transfer it to a secure account that was set up for her. She did — and lost $8,000 to impostors.

4. Student-loan con

A couple in Indianapolis got a call from someone who stated his government agency was handling the ​student-loan-forgiveness debt-cancellation program that President Biden had signed into law. The caller just needed their Social Security and banking information to complete the application. The couple complied, but then they grew suspicious and reported the encounter to the bank in time to stop any losses.

5. FBI flimflam

A 79-year-old Pembroke Pines, Florida, man was contacted by a fake FBI agent who said he had won a $1.9 million sweepstakes, but the money was being held until he could pay fees and taxes. He eventually sent $100,000 to what he believed was the FBI consumer affairs branch, and the money has not been recovered.

The bottom line: Don’t let your instinct to cooperate with someone claiming to be with the federal government be your downfall. This list of government practices should help you spot impostors.