FBI Director Christopher Wray on Thursday said there is "no question" that cartel activity from Mexico is "spilling over" into the U.S. – as the country faces a historic crisis at the southern border triggered by a massive surge in migration.

Wray was asked at a House Judiciary Committee hearing by Rep. Tom McClintock, R-Calif., whether his agency knew of instances where foreign nationals coming across the border were deeply indebted to cartels and smugglers.