AN Italian businessman who was helping police break organised crime gangs that operate waste disposal rackets in Naples was gunned down in an apparent mafia hit, police said.

The latest killing in the southern Italian city, which in recent months has become as famous for its piles of trash as for its reputation for crime, came on a day that thousands of people attended a rally against plans to open new rubbish dumps.

Police said Michele Orsi, a businessman with mafia links who had turned informant, was shot three times near his home by assailants who were lying in wait.

Orsi, who worked in the waste disposal business, had spent time in jail last year during an investigation into mafia involvement in the trade. He turned informant and gave evidence against a suspect at a court hearing two weeks ago.

"The case is even more serious than previous ones. This was a businessman from the Caserta area (of Naples) who, although he had colluded with organised crime, was helping investigations,'' said anti-mafia investigator Franco Roberti.