More than a dozen horses were killed when fire swept through their Adams County, Colorado, barn this week.

Brighton Fire Rescue District Public Information Officer Natalie Ridderbos said that in the early hours of Dec. 13, fire department personnel responded to a call from a neighbor who reported seeing smoke rising from a location nearly a mile away from her home. When crews arrived, firefighters discovered a horse barn completely engulfed in flames. A group of 15 horses were residing inside the structure at the time of the fire.

“Unfortunately, all of them died,” Ridderbos said.

Whether the facility was used as a boarding barn remains unknown, she said