Police smashed a huge illegal toxic waste disposal ring on Wednesday which they said had illicitly dumped some 100,000 tons of hazardous material in northeast Italy over a period of two years.
A total of 11 suspects were arrested and 135 more placed under investigation.
Police said at least 70 companies were involved and that dozens of offices, dump sites, waste disposal plants, trucks and caves had been seized or condoned off.
Those arrested face a range of charges including waste trafficking and fraud.
Prosecutors said the crime ring operated in the Marche, turning the central region into the rubbish tip for toxic industrial waste produced across the north, particularly Veneto and Lombardy.
The waste, which included asbestos, chemical sludge, paint and bitumen, was trucked into the Marche and then disposed of in illegal dump sites and caves.
The waste arrived at a rate of six to seven truckloads per day during the period 2003-2005, prosecutors said, with 40,000 tons being illegally dumped around the city of Pesaro alone.
Sometimes the hazardous material was taken to legal, council-run dump sites with the complicity of local administrators and public-appointed waste managers, investigators said.
Several local officials are under investigation for failing to monitor the situation and inspect dump sites.
Workers at the legal dump site of Fano told prosecutors that they began suffering from a range of complaints including skin irritations after dealing with what they thought was ordinary urban waste.
In reality, the waste had been mixed with hazardous materials including lead, zinc, chromium and copper.
Prosecutors said dangerous industrial waste was regularly washed down with water and then fraudulently classified as non-toxic before being sent to normal dumps and incinerators.
In at least one case, toxic materials were dumped on land where it could have contaminated water sources.
Police said they were prevented from making more arrests under the terms of a recent prisoner pardon approved by parliament which benefits those who have committed crimes prior to May 2006, regardless of whether they have been discovered yet or not.
Waste disposal is a growing concern in Italy, where organised crime groups have made turned it into one of their most lucrative businesses.
According to Italian environmental organisation Legambiente, waste trafficking nets the country's mafiosi some 22 billion euros a year.
Earlier this month, protesters from Naples gathered in Rome to demonstrate against the illegal dumping by Mafia-controlled businesses of millions of tons of toxic waste.
The protesters said the dumping was to blame for rising cancer rates in areas around the southern city and blasted the government for not doing enough to combat the problem.
Since the 1970s, some 4 million tons of industrial waste has allegedly been dumped on fertile Neapolitan lands where tomatoes are grown and where buffaloes used to make the region's famed mozzarella cheese graze.
The waste is believed to have poisoned the soil and water with carcinogenic dioxins.
