The RAF helicopter that crashed in Afghanistan killing five people may have been caused by a collision with a security surveillance balloon.
New video footage, obtained by Sky News, shows the balloon falling to the ground following the crash.
US Colonel Brian Tribus said that an "incident" involving a NATO aircraft and an observational balloon had taken place "in the vicinity of the Resolute Support base", during which the balloon was severed from its mooring.
In earlier reports, an Afghan security guard who witnessed the incident said the helicopter "hit the cable of the security balloon over the base. It seemed like the cable was turned around the helicopter rotor".
The accident occurred on Sunday when a UK Puma MK 2 aircraft attempted to land at the headquarters of Nato's Resolute Support mission in Kabul, according to the Ministry of Defence (MoD).
Two RAF personnel were among those killed in the crash.
The MoD said the two British RAF staff were from the 230 and 33 Squadrons, which are based at RAF Benson, south Oxfordshire. An MoD spokeswoman said their families have been informed.
The three others who died were Resolute Support personnel, a spokesman for the mission said.
Resolute Support is the Nato-led mission that seeks to train Afghan security personnel since the International Security Assistance Force (ISAF) was stood-down in 2014.
An investigation is under way into the accident.
