The Federal Aviation Administration says helicopters will be permanently banned from flying near Washington, D.C.’s airport on the route where an airliner and an Army helicopter collided in midair.

The closure of the helicopter route near the airport makes permanent restrictions put in place after the January 29 mid-air collision.

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

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 restriction is on the same route where a passenger jet and an Army helicopter collided in midair, killing 67 people.

The Federal Aviation Administration said Friday it is imposing permanently restrictions on non-essential helicopter operations around Washington Reagan National Airport and eliminating helicopter and passenger jet mixed traffic.

The US Federal Aviation Administration detailed a series of restrictions on helicopter traffic near Ronald Reagan Washington National Airport following a deadly midair collision in January.