Aviation authorities on Friday permanently closed part of a helicopter route east and southeast of Reagan National Airport where an Army Black Hawk collided with an airliner in January, killing 67 people,

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.

Aviation officials on Friday announced permanent curbs on helicopter traffic near Reagan National Airport, the site of a collision involving an Army Black Hawk and American Airlines flight that killed 67 people in January.