Families of victims visit Washington plane crash site amid swirl of questions

Federal investigators are still working to piece together the events that led to the crash that killed 67 people

Families of victims of the deadliest US air disaster in nearly 25 years visited the crash site on Sunday amid a swirl of ongoing questions on what caused the mid-air collision between a passenger jet and a military helicopter at an airport just outside Washington DC.

Dozens of people walked along the banks of the Potomac River near Reagan National airport, close to where an American Airlines jet and an Army Black Hawk helicopter crashed into each other on Wednesday, killing all 67 aboard.