If you get a letter from a law firm or asset management firm about inheriting millions from someone who shares your last name, be very wary. If you answer, you’re most likely going to lose money, personal data – or both.

The letters, which are a type of inheritance scam, have proliferated lately, according to news reports and the Federal Trade Commission. The scammers typically want you to respond fast and keep the transaction secret.

“It might be tempting to reply, just to see if you really can get some of the money. But that’s where the scam kicks in. If you contact them, they’ll try to get your personal and financial information, like your Social Security or bank account numbers, your money – or all of the above,” the FTC writes in its July Consumer Alert.

One letter, obtained by Scam Watch, was postmarked in Canada, though it supposedly came from an investment advisor in Belgium. The scammer writes that if you partner with him, he’ll split $9.7 million euros with you in a “risk free” transaction that requires your utmost discretion since “we are not quite sure if you’re really related.” All you have to do is answer the letter via email and follow the instructions that follow. “If this business proposition offends your moral values, do accept my apology,” the scammer writes.

If you get one of these letters, the FTC advises that you ignore it. While it is possible that a distant relative may have left you a windfall, such notifications should come from a legitimate law firm or the probate court. They will not ask you to keep it secret, pay upfront fees, or claim half the money. If you think the letter may be genuine, you should independently confirm the source’s address and phone number and make sure the writer is trustworthy. The likelihood that it is legitimate is very small,

The FTC also suggests you alert friends and family, since they may not realize these types of letters are scams. According to a survey by Visa, about 15 percent of Americans have been targeted by inheritance scams.