Italian authorities have searched the headquarters of Volkswagen Italia as part of a local investigation into the emissions testing scandal at the German automaker.

The financial police in the northern city of Verona conducted the searches on Thursday and confirmed that there are officials under investigation. An official at the provincial police headquarters declined to identify those under investigation.

Volkswagen has said around 11 million cars worldwide were outfitted with software that enabled them to evade diesel emissions testing.

Volkswagen bought a full-page advertisement in Turin daily La Stampa on Tuesday apologizing for the "grave error" and promising to do everything to win back the trust of Italians.