FAA halts all departing flights across the United States

The Federal Aviation Administration has ordered all flights across the United States grounded, halting departures nationwide and citing safety concerns.

All departing aircraft are to remain on the ground until further notice, the FAA said.

International flights arriving in the United States will be handled on a case-by-case basis.

The agency has not publicly explained what prompted the order. A nationwide grounding of this kind has been imposed only one other time since 9/11.