A storage container at a construction site for the TAV rail project in the Susa Valley east of Turin was set ablaze early Thursday, Italy's ANSA news agency reported.
Investigators also found tear gas shells at the scene and the words "No TAV" scrawled on the equipment.
The project has cause controversy in Italy for several years. Opponents of the project say the railway, which will run high-speed trains between France and Italy, will harm the environment and cost the public too much money.
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