The federal government has resumed checking the fingerprints of people other than parents who care for migrant children detained at the border.

The measure comes amid concern by immigrant advocates that skipping the screening could put children at risk.

Kenneth Wolfe, a spokesman for the Administration for Children and Families, said late Wednesday that the agency has gone back to a previous policy of only exempting parents and legal guardians from having their fingerprints taken.

But he says that no child was harmed by the more lax fingerprint policy.

The number of Central American children apprehended at the border with Mexico has surged in recent weeks.

Advocates say rising gang violence and threats have driven the children to leave their countries and trek across Mexico to reach the United States.