Three Bayern Munich football stars have been named in a death threat letter that called for the ‘dirty Bavarian pigs’ to be shot.

Robert Lewandowski, Manuel Neuer, and Serge Gnabry were mentioned in the anonymous letter which, was delivered to the officers of second division team St Pauli.

Police in Hamburg are examining the note for fingerprints and DNA traces with Bayern and the German football authorities put on alert.

German newspaper Bild report the letter arrived at Hamburg-based St Pauli on January 12 and was headed: ‘Save the league, save football. Fire and death to the dirty Bavarian pigs.’

It named the three players with the author calling for them to be shot and made threats to Bundesliga referees.

The letter was passed on by St Pauli to police detectives at the famous Davidwache station near the Reeperbahn.

The German State Criminal Police Office (LKA) have contacted colleagues around the country to see if any other letters have been sent and also informed the Football Association.

A police spokesman told Bild: ‘We are investigating on suspicion of threatening and disturbing the public peace by threatening to commit crimes. We will check the backgrounds.’