WASHINGTON (AP) — Federal investigators looking for the cause of the January collision between a passenger jet and an Army helicopter near Washington, D.C., that killed 67 people recommended a ban on some helicopter flights Tuesday to improve safety, saying the current setup “poses an intolerable risk.”

The National Transportation Safety Board is seeking more flight restrictions on helicopters around Ronald Reagan Washington National Airport. The NTSB's "urgent" recommendations come more than a month after a Jan.

A helicopter flight path over a Washington DC airport should be banned after a crash which killed 67 people, federal investigators have recommended.