French police say vandals have desecrated nearly 150 Muslim grave sites at a World War I military cemetery in northern France.

Authorities say headstones were inscribed Saturday night with anti-Islamic slogans and graffiti deriding Justice Minister Rachida Dati, who is of North African origin. A pig's head was found hanging from one grave marker.

French President Nicolas Sarkozy called the vandalism a form of "unacceptable racism." He said he shares the pain of his country's Muslim community - the largest in Europe.

The desecration came less than a year after youths painted Nazi inscriptions and swastikas on Muslim tombs in the same cemetery.

Police arrested two suspects in the 2007 vandalism. Both were convicted and sentenced to one-year prison terms.

From 1914 to 1917, France mobilized about 600,000 colonial subjects, including many Muslims from Algeria and Tunisia. Seventy-eight thousand of those conscripts were killed.

Some information for this report was provided by AP and Reuters.