investigators believe gang bangers armed with military assault weapons shot up cornell square park in the yards neighborhood. >> illegal guns. illegal guns. illegal guns drive violence. military-type weapons, like the one we believed to have been used in this shooting belong on a battlefield, not on a street or in a corner or in a park in the back of the yards. it's a miracle, in this instance, there have been no fatalities. >> is this a setback to the efforts you've had and the announcements you've made that violence is down in chicago and 13 people shot and 24 shot overall in the past 24 hours. is this a setback? >> every time somebody is shot in the city it is a setback for us. the fact is, there is a structural problem with our laws that facilitates the flow of illegal guns to our streets. >> the fbi last week called this city the murder capital. how do you get rid of that image in the rest of the country? >> we keep knocking down the murder rate like we are now. this is not the time to talk about statistics. so i'm not going to do that. >> this story will be on every network news