Pistoia, May 10 - Italy's first black minister, Integration Minister Cecile Kyenge, received the latest in a spate of racist insults Friday. "Shoot Minister Kyenge, not Carabinieri" and "Minister Kyenge, f**k off" were found daubed on walls in the Tuscan city of Pistoia, signed by supporters of the far-right Forza Nuova party. The first taunt referred to a man who shot two Carabinieri outside the premier's office while Democratic Party (PD) deputy head Enrico Letta's new left-right government was being sworn in nearby. On Thursday Forza Nuova party hung a banner outside the PD offices in the Marche city of Macerata that read: "Kyenge go back to Congo". Italian prosecutors have opened a probe into online abuse directed at PD member Kyenge, a doctor who was born in the Democratic Republic of Congo who has said she will push for migrant detention centres to be closed and for children born to migrants on Italian soil to get automatic citizenship. Forza Nuova is against a proposal by PD Senator Mario Morgoni for Kyenge to be made an honorary citizen of the Marche city. As well as anonymous attacks on the Internet, the 48-year-old Kyenge was also targeted by a senior member of the the anti-migrant Northern League. League MEP Mario Borghezio called Letta's new executive a "bonga bonga government" and claimed Kyenge would seek to "impose her tribal traditions from the Congo". An online petition has been launched calling for Borghezio to be ousted from the European Parliament.