Crews return to Potomac River to recover wreckage from Washington air disaster

Rescue and salvage crews with cranes work near the wreckage (Jose Luis Magana/AP)

Crews are back at the Potomac River to retrieve the submerged wreckage of an airliner and an army helicopter that collided in mid-air last week in the deadliest US air disaster since 2001.

Authorities have recovered and identified 55 of the 67 people killed in the crash and Washington DC Fire and EMS Chief John Donnelly has said they are confident all will be found.