The Federal Bureau of Investigation is probing the suspicious buyout bid for cosmetics company Avon Products Inc by purported acquirer PTG Capital Partners, an agency official said on Friday.

The news was earlier reported by the Wall Street Journal, which said the FBI review was in its preliminary stages.

The U.S. Securities and Exchange Commission, which was running a separate civil probe, has shared information with the FBI, the report said, citing people familiar with the matter.

The apparently non-existent firm on Thursday offered to buy Avon for almost thrice its market valuation.

PTG Capital Partners said in an SEC filing on Thursday that it would pay $18.75 per Avon share, sending the company's stock up as much as 20 percent.

According to the SEC's Edgar company database, PTG is incorporated in British Indian Ocean Territory, an archipelago between Africa and Indonesia with no civilian population, according to the CIA's fact book.

A spokesman for the UK Foreign Office said there was no corporate register in this territory.

Avon, whose shares were marginally up in after-market trading, said it hadn't received any takeover bid.