Immigrants deported to their home countries have been killed after their return. 

Constantino Morales, an undocumented advocate who lived in Iowa for five years and was twice denied asylum in the United States, said he couldn’t return because he had been a police officer who stood up to drug traffickers. 
He was murdered six months after his deportation. 
At least five children were murdered in Honduras soon after the U.S. government deported them in 2014.

 A Mexican domestic violence victim was killed by her boyfriend and left in a burnt-out car five days after her deportation.

There's plenty more stories just as tragic and just as avoidable.