Seven firefighters were injured outside Naples in an attack near a toxic dump at the centre of an ongoing waste disposal crisis.

Some 30 assailants, described by the domestic ANSA news agency as hooligans, hurled powerful firecrackers into a firetruck, where they exploded, injuring the seven firefighters.

Masked men also hurled stones at a police car, ANSA said.

Since the waste disposal crisis developed late last month, with more than 100,000 tonnes of uncollected garbage accumulating in Naples' Campania region, protests have turned violent on a nightly basis in and around the Pianura dump in the western suburb of Pozzuoli.

Press reports say small groups of protesters or hooligans have begun gathering at other sites on the outskirts of Naples seeking confrontation with security forces.

Italian Prime Minister Romano Prodi yesterday unveiled a campaign to bring a definitive end to a recurring overload of the region's dysfunctional waste disposal system.

Troops will be deployed to help clean up the hardest hit areas, and rubbish will be trucked to landfills in other regions under the four-month plan.

Many of the landfills in Campania are controlled by the regional Camorra mafia, who make a lucrative business out of subverting waste handling procedures and shipping in industrial waste from the north.

Since 1994 when the government decreed an "emergency situation" in the region, several dumps infiltrated by the mafia have been closed and companies investigated, though none has been convicted.