A leading German Jewish campaigner has received a death threat after calling for the far-right Alternative for Germany (AfD) to be banned in the wake of its victory in the eastern state of Saxony-Anhalt.

The Munich prosecutor's office sad on Friday it has launched an investigation into the threat against the 93-year-old Knobloch, the leader of the Jewish Community of Munich and Upper Bavaria.

Andreas Franck, the anti-Semitism commissioner at the prosecutor's office, told dpa he has opened investigations into suspected incitement to hatred, threats and criminal damage.

A witness discovered the scrawled threat on a park bench and a rubbish bin in the English Garden in Munich on Thursday and informed police.

Knobloch subsequently cancelled her attendance at an event.

The threat was explicitly linked to the AfD's election victory in Saxony-Anhalt. The community confirmed that Knobloch was threatened by name.

Among the graffiti was a Star of David, Franck said.