A family of three who set off on a hike with their dog in Northern California last week have all been found dead with no clear explanation. According to the Associated Press, a family friend reported the family missing on Monday, only for their bodies to be discovered in a remote area of Sierra National Forest hours later. The family has been identified as John Gerrish, Ellen Chung, and their 1-year-old daughter, Muji. The body of their family dog was also found at the scene. Kristie Mitchell, a spokeswoman for the Mariposa County Sheriff’s Office, said there was no immediate explanation for their deaths, but investigators are treating it as a hazmat scene. “It could be a carbon monoxide situation,” said Mitchell. “That’s one of the reasons why we’re treating it as a hazmat situation.” Sheriff Jeremy Briese said in a statement: “This is never the outcome we want or the news we want to deliver. My heart breaks for their family.”