Transcript for Trump defends using tear gas on migrants at US-Mexico border

Overnight president trump defended the use of tear gas on migrants who rushed toward the fence, some of them children and Matt Gutman is at the board in Tijuana, Mexico. Reporter: Even as they called for an investigation into the use of tear gas on children, president trump doubling down overnight disputing without evidence whether those parents we saw clutching those children and those clouds of tear gas were actually their parents. This morning, the migrant caravan arriving at the border continues to grow expected to reach 9,000 in the coming days, but also licking its wounds after clashing with U.S. Customs and border police agents on Sunday. A contingent of migrants rushed the fence met by a wall of tear gas. Frantic mothers and their children caught in it. President trump without evidence disputing that the migrants were the children's parents at all. How did you feel when you saw the images of -- I say, why are they there? First of all, the tear gas is a minor form of it and it is safe. These are grabbers. They grab a child because they think they'll have a certain -- they'll have a certain status by having a child. Reporter: ABC news embedded on and off with the caravan for over a month but has seen no evidence of so-called grabbers. And secretary of homeland security kirstjen Nielsen saying in a statement, the limited number of women and children in the caravan are being used by the organizers as human shields. This is putting vulnerable people in harm's way. But some here like those who tried to rush the fence say they've had enough. He says now he wants to go back. Yesterday was too scary and just wants to go home. Now, the Mexican government said overnight over 100 migrants like Duval who we interviewed have asked to be repatriated back to their home country and the mayor of Tijuana called this a humanitarian crisis, one that is only set to grow as thousands of additional migrants are expected here over the coming days. Robin. Thank you.

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