Families are sending children alone across the southern border in response to Biden administration policies, according to a person familiar with the situation, putting them at risk and adding to the danger of the situation.

The families are exploiting Biden administration rules against immediately returning unaccompanied children from countries other than Mexico, said the individual with knowledge of discussions at the Department of Homeland Security. The policy has created a loophole for families who have been turned away after they illegally came over the border and were pushed back into Mexico by Border Patrol.

Immigration lawyers told NBC News that the strategy presents the best chance the children will be able to stay in the United States after being released to a sponsor in the country, even if it means the parent cannot go with them.

Of the more than 18,000 family units who illegally came across the border last month, 8,000 were returned south of the border, federal data from February show, providing thousands of parents the opportunity to decide to send their child back over the border unaccompanied.

Single adults are still being immediately turned away after coming into the U.S. illegally. {snip}

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