(ANSA) - Rome, July 27 - Police say they arrested five foreigners Friday carrying gas masks, body protection and knives to protesters rallying against the proposed high-speed train linking Italy and France. Two French citizens, a Belgian, a Swiss national and one from Greek face charges after their car was searched by police. Violence has been increasing around the construction site in northern Italy between police and demonstrators who fear the 15-billion euro high-speed rail plan will create serious environmental harm. Governments says the rail line, known as TAV, is vital to improving transportation links for Italy. Meanwhile, anti-TAV messages were found written in large white letters on the facade of a church in Florence's Piazza Isolotto Thursday night.