Americans are likely to be seeing more drones in the night sky, but there's no evidence of foreign involvement or a national security risk, Homeland Security Secretary Alejandro Mayorkas said.

"I want to assure the American public that we are on it," Mayorkas said on ABC's This Week. His appearance on a Sunday morning network show signaled a stepped-up response by President Joe Biden's administration to address surging public concern about the sightings.