The 42-year-old dentist told police two men entered his practice March 26 and attacked him, The Local.de reported.
He said the robbers cut off his left index finger with a pair of garden shears after they demanded money.
However, police said they didn't find any trace of robbers and prosecutors said they now believe the dentist may have lied about the whole incident for an insurance payout.
"We are investigating on suspicion of an attempted fraud and faking of a criminal offense," public prosecutor spokesman Tom Kopping told the Berliner Zeitung newspaper.
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