The vast majority of immigrant children who arrive alone at the U.S. border are placed by the government with adults who are in the country illegally.

That's according to federal data reviewed by The Associated Press.

The government has long said that it places the children with family and friends regardless of immigration status. But since more children began arriving on the border in 2014, officials have not revealed how often those sponsors lack legal papers.

In response to a Freedom of Information Act request, the Department of Health and Human Services provided data on the 71,000 mostly Central American children who were placed with sponsors between February 2014 and September 2015. Eighty percent were sent to sponsors who were not here legally.