An actor was struck in the back of the head by a drone during filming in a quarry in south Wales, according to an air accident report.

The incident at Morlais quarry in Merthyr Tydfil on 19 July 2022 saw 50 actors and horses halted while he received medical attention.

The Air Accident Investigation Branch (AAIB) said an actor deviated from the briefed path and ran into one of the drone's propellers.

The actor had "superficial injuries".

Before the day's filming began, the experienced pilot gathered the crew, production staff and actors together to conduct a safety briefing, according to the report.

After two "shoots" were completed successfully, there was a further sequence involving a tracking shot of actors and horses running past the drone which was to hover at low head height.

The drone, a DJI Inspire II, had to be flown slowly backwards as the group of actors ran towards it, before the group split into two streams to avoid the aircraft.

As one of the actors moved to the side and drew level with the drone, he suddenly cut across its flight path towards the other stream of actors and collided with the propellers.

The aircraft was immediately flown out of harm's way and filming was stopped while the actor received medical treatment.

Following the accident, the Civil Aviation Authority (CAA) updated its guidance to reflect the difficulties of filming close to a large number of third-party individuals.

The AAIB said the drone operator and film director agreed to complete "walk-throughs" of each scene with the actors and film crew before filming starts.

More time has been allocated for setting up close proximity shots and the drone operator has updated risk assessments, the report added.