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 are recommending a ban on some helicopter flights.

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.

The NTSB has recommended a permanent ban on helicopter routes near Ronald Reagan Washington National Airport following a January crash, citing safety concerns.