Media playback is unsupported on your device Media caption The demonstrators demanded an immediate clean-up of the contaminated land, as Tim Allman reports.

Tens of thousands of people have protested in Italy's southern city of Naples against illegal dumping of toxic waste blamed on the local mafia.

Demonstrators carried photos of relatives who they said had died of cancer as a result of the pollution.

Locals call the area between Naples and Caserta the "Triangle of Death" because of toxic fumes after waste burning.

Some 10 million tonnes of industrial waste has reportedly been dumped in the region over the past 20 years.

Environmental group Legambiente, which organised Saturday's protest, said nearly 440 businesses in central and northern Italy had been taking part in the illegal activity.

"It is essential that in addition to waste we find also the truth about who is responsible," Legambiente's director Rossella Muroni was quoted as saying by the Associated Press.

The demonstrators also demanded an immediate clean-up of the contaminated land.

As more and more illegal dumps are found, the Italian government says it is starting an extensive project of cleaning the contaminated area.

The local mafia, the Camorra, is suspected of securing lucrative contracts to dispose of waste and then dumping much of it illegally.

Two decades ago doctors noticed that incidences of cancer in towns around Naples were on the rise.

Since then, the number of tumours found in women has risen by 40%, and those in men by 47%.