The bill collector phoning you could be a fake, AARP is warning seniors.

Tell-tale signs the caller may be seeking money that is not really owed include someone who is trying to collect on a loan the senior doesn’t recognize, refuses to give out a mailing address or phone number, asks for sensitive information or makes threats, noted an AARP Fraud Watch alert Wednesday.

To protect themselves against fake bill collectors, AARP said a senior should not agree to discuss a debt on the phone unless the caller sends a written notice first with the name of the creditor, the amount of the debt and the senior’s rights under the Fair Debt Collections Practices Act.

AARP said seniors should also refuse to give out bank account, credit card and Social Security numbers over the phone whether they think the debt collector is legitimate or not.

The group said crooks use the scam to steal money from seniors through purchases on the victims’ credit cards, write fraudulent checks and taking out loans in the names of their targets.