Transcript for Trump suggests troops can shoot at migrants on the border

We begin with president trumps closing argument ahead of Election Day taking his new plan to crack down on illegal immigrants directly to his many voters as possible in a pitch to supporters in Missouri last night the president continue to stoke fears about. That migrant. Caravan heading north to the U less he's now proposing a major change at the border while suggesting that migrants. Could be shot if they pose a danger to US troops. ABC's lot of Zach is covering it all from DC good morning Donna. Good morning to you can defend Lindsay president trump says. That he will change the rules of asylum saying that he will deny asylum to anybody entering the country illegally. Instead he argues that they must present at ports of entry where he says they will be held now in tent cities. What not and that our country. Just days before the midterm elections president trump is campaigning hard against a group of migrants Seeking Asylum and illegal immigrants. But you don't lot of Mac it to be overrun by masses of illegal aliens. And giant caravans you better vote Republican. The president says he may deploy up to 151000. Military troops to the US border that's roughly the same number deployed to fight the telemann in Afghanistan. Under the law the truth of the border are only supposed to offer logistical support for the Border Patrol. But the president said military force could be engaged continue to migrants throw a rock. Will get a considered I jump consider rifles. When they throw rocks like they did at the Mexico military police I say consider it a rifles. Those comments prompted general Martin Dempsey the former chairman of the Joint Chiefs of Staff to tweet. A wasteful deployment of over stretch soldiers and Marines would be made much worse if they use force disproportional to the threat they face. They won't. President trump also announced he would be making changes to the asylum seeking process pledging to help migrants in ten cities along the border believing that in the final days before the election that argument will mobilize voters NX. Key demographic I don't want him in our country. And women don't want them in our country. According to the latest ABC news Washington Post poll independents have expressed broad dissatisfaction with president trump so turning around the base becomes essential for Republicans. Lindsay Kenneth to clock ticking down to Election Day Leno Zack thank you.

This transcript has been automatically generated and may not be 100% accurate.