Muir. We begin with America on high alert this fourth of July. Police ratcheting up security across the country. Officers out in full force. At tourist attractions, checkpoints set up. And in Boston,... See More
Muir. We begin with America on high alert this fourth of July. Police ratcheting up security across the country. Officers out in full force. At tourist attractions, checkpoints set up. And in Boston, the commissioner saying a lone wolf attack is their worst nightmare. Here's gio Benitez. Reporter: Tonight, a nation on alert. In Washington, D.C., U.S. Park police are on horseback at the national mall. We are aware of the chatter, and we take those into account. Reporter: Authorities worried about lone wolves. And in Boston, police are deplodepl deploying special teams. Memories of the Boston bombing still fresh, preparations, up to a half million people could attend. Reporter: In Chicago, huge events. Alex Perez is there. It will be a busy one. Big crowds expected everywhere. The cubs and white sox at home, three huge grateful dead converts. Reporter: And in Los Angeles, 300,000 people expected at events. Authorities asking people to be on the lookout. Reporter: And in New York, officers patrolling from the ground, sky and water. Obviously, this is a very important area. Look what's behind us. So many people will be focused on this area. There will be large amounts of crowds, so we have increased patrols. We're here for the safety of the citizens on the water. Reporter: Here in New York, officials say besides the officers patrolling the streets, they will add another 7,000 officers this weekend alone.
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