United Kingdom, Oct. 11 -- Oliver Stark and three others have been injured on the set of 9-1-1.

The 35-year-old actor broke his ankle while performing a stunt on the ABC show - in which he plays Evan "Buck" Buckley - at the end of August and required surgery, but has since returned to work, while other performers have also suffered stunt-related injuries in unrelated incidents, putting the programme's safety protocols under scrutiny.

Sources told Deadline the stunt that led to Oliver's injury involved a firefighter swinging from a car over a set piece to the ladder truck, and during rehearsals, a stunt double suffered a sprained ankle but no injury report was submitted because they declined medical treatment.

The typical process on the...