French police arrested 100 protesters after violent anti-NATO demonstrations in the French city of Strasbourg today, one day before leaders from the 28-member alliance were due to meet, dpa quoted a police spokesman as saying. Demonstrators hurled rocks and attacked a military vehicle, breaking the windows. Store windows were also shattered and trash bins were set aflame before police fired tear gas canisters and order was restored. The demonstration turned violent after police prevented some 600 protesters from marching into downtown Strasbourg. Germany and France have both launched major security operations to keep order during the two-day summit, which marks the 60th anniversary of NATO's founding. The summit will take place in Strasbourg and the German cities of Kehl and Baden Baden, across the French border. Some 14,600 police will be guarding the 3,500 delegates on the German side, while 10,000 will be patrolling the streets of Strasbourg, where most of the talks will be held.