The Federal Aviation Administration (FAA) has announced the permanent closure of a helicopter route near Washington DC's airport where a fatal midair collision involving a passenger jet and an Army helicopter resulted in the tragic deaths of 67 people.

The closure comes after crash investigators said there was a history of safety risks near the busy airport that had gone unaddressed.

The move follows federal investigators's call for a ban on helo flights on the route, citing a string of near misses in recent years.