Seven people, including three children, were found dead at a home in Minnesota this weekend—but police say there’s no evidence of forced entry or violence at the scene. According to CNN, family members were carrying out a welfare check at the home in South Moorhead on Saturday night when they discovered the bodies and called for help. The Moorhead Police Department said in a Monday statement that a preliminary autopsy had “ruled out any obvious trauma as the cause of death,” but that blood samples were undergoing “further investigatory examination.” The deceased were identified as Belin Hernandez, 37; Marleny Pinto, 34; Eldor Hernandez Castillo, 32; Mariela Guzman Pinto, 19; Breylin Hernandez, 16; Mike Hernandez, 7; and Marbely Hernandez, 5.

The Kachuol family lives on the same street as the victims, and they spoke to Valley News Live a day after the bodies were found. “I had a really hard time sleeping. All I could think about was them dying. I was trying to figure out how they died, and I was really scared,” said Esther Kachuol. Josiah Kachuol added: “I thought something bad happened to them like murder or something, but I learned it’s an accident. It’s just really heartbreaking.”