Lifestyle Pets HBO Insists Horse That Collapsed on 'The Gilded Age' Set Died of Natural Causes, as PETA Demands Investigation HBO said that a carriage and two passengers were involved in the scene but production stopped once the horse showed signs of ailment By Amanda Taylor Amanda Taylor Digital News Writer, PEOPLE People Editorial Guidelines Published on July 9, 2022 04:46 PM Share Tweet Pin Email Photo: Alison Cohen Rosa/HBO HBO is addressing the death of a horse on the set of a TV drama. Following the incident, which occurred while filming The Gilded Age, PETA wrote an open letter to HBO demanding that the network shows accountability and reevaluates its animal wrangling practices. According to alleged reports made to PETA from The Gilded Age set, the horse experienced head trauma that led to it "severely frothing" at the mouth. HBO confirmed the horse's death and cited "natural causes," but PETA wants the network to look further. PEOPLE reached out to HBO, which provided more context and information about the on-set experience of their horses and the death of the animal in question. The network says the 22-year-old horse had prior filming experience and the tragic incident took place while filming a scene 15 minutes after a one-hour rest period. Ringling Bros. and Barnum & Bailey Circus to Return in 2023 with Revamped Animal-Free Show Alison Cohen Rosa/HBO Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. HBO said that a carriage and two passengers were involved in the scene but said that once the horse showed signs of ailment, production stopped immediately and then wrapped for the day. "HBO was saddened to learn that on June 28, during filming on the set of The Gilded Age, a horse collapsed and died, likely of natural causes, according to a veterinarian's preliminary findings," the statement to PEOPLE said. "The safety and well-being of animals on all our productions is a top priority, and the producers of The Gilded Age work with American Humane to ensure full compliance with all safety precautions. Following AHA's recommendation, the horse was transported to a facility for a full necropsy. AHA has interviewed all involved personnel, and full necropsy results are pending." Louisa Jacobson Says Gilded Age Corset Was so Tight It Hurt Her Ribs: 'Couldn't Sleep on My Side' Further information from HBO stated that horse wranglers, as well as a veterinarian, confirmed the horse hadn't displayed signs of discomfort in the outdoor environment when the temperature was in the 70s. The network insisted the animal had not been overworked. The Gilded Age, created by Julian Fellowes and starring Nathan Lane and Christine Baranski, depicts life before automobiles. As such, there are many horses on set and on screen in the show, which is set in the late 1800s. RELATED VIDEO: Catskill Animal Sanctuary Helps Horse That Lost His Eyesight Ten years ago, on the set of HBO's Luck, three horses who were filming died. In a letter from PETA's Animals in Film and Television Coordinator, there is a reminder of that incident and the commitment the network made following it to honor their animal costars. "We had hoped HBO might have learned something from that experience: namely, that horses aren't props. They're sensitive animals who can be startled easily, and they must be gradually accustomed to the changing conditions on a set," PETA wrote. " "They should not be used in film or television productions at all. If they are, an equine behaviorist should be on set at all times, and this person must be given the authority to stop filming if horses begin to show what are often subtle signs of agitation."