Transcript for DHS chief examining immigration enforcement on US-Mexico border

A crackdown at the border hundreds of children separated from their parents if they crossed into this country illegally even if they're applying for asylum. The parents in many cases incarcerated to children can be sent a thousand miles away. ABC's chief national affairs correspondent Tommy Thomas with one mother who son was taken from her eight months ago and authorities can't tell her when shall see him again. Thomas just back from the border tonight. Homeland Security secretary cures to Nielsen on the southern border tonight. Giving it up close look at immigration enforcement this week but behind the scenes all hardline tactic underweight. Separating immigrant families that cross illegally into the US including asylum seekers if you don't walk your child to be separated. And our bring them across the border illegally. At least 700 children have been separated from their families since October it happened to this mother Jocelyn. Who says she was fleeing an abusive husband back home in Brazil. When she and her fourteen year old son crossed illegally her son was taken from her but yeah. Oh it. She says he looked at me like mom help meet because I don't know where they're taking meet. Her son taken more than 1000 miles away to live in a facility in Chicago. They haven't seen each other in more than eight months. After 25 days in an El Paso jail she's now living in a shelter waiting for the government to rule on her asylum status. With the help of the ACLU she's suing to get her son back immigration advocates say they'd never seen anything like this. Literally three euros for a fiber of begging. Screaming please don't take me away from my mommy and they're just being ripped away. As neutral administration insists. There simply prosecuting the crime. If that parent has a four year old child what he planned to note that the child under long goes to HHS her care in custody they will be separated from their parent just like Michael my in the United States every day. And the president somehow blaming this on Democrats the Democrats gave us that look so horrible thing we have to break up. But lawmakers and immigration advocates say that's simply not true that this enforcement is to scare people from entering the country illegally. Now as for Jocelyn and her son they are hopeful they will be reunited soon but right now. Hope is all they have the court has yet to decide on their case. And health officials have now warned about the long term psychological damages these long term separations could have. On those children David and Tom in understand this story great to have your test tonight.

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