hi, i'm drew griffin. don lemon on assignment tonight. it's a gathering of the world's most powerful people, the g-20 summit join the political and financial leaders of the wealthiest most powerful countries on the globe. president obama spent part of the day discussing the world economy with people like the presidents of korea and china. but outside the secure meeting, protesters turned out clashing with police, shattering storefronts and setting fire to police vehicles. we've just learned more than 130 people have been arrested so far. toronto's police chief says his officers are on top of the situation. >> tonight, we began removing members of the mob from our streets and so far tonight 75 persons have been taken into custody. these arrests will continue as is necessary. those responsible for acts of vandalism will be held accountable.