Roger Hanna Morash, 35, and Valerie Morash, 32, were found dead in their Berkeley apartment on Jan. 23 alongside their two cats, and authorities still aren't sure exactly what happened—which is a big concern for the tenants of the other three units in the building where the couple lived. Medical examiners and veterinarians ultimately determined that accidental carbon monoxide poisoning killed the Morashes and their cats, but they haven't been able to figure out where the carbon monoxide came from. No carbon monoxide was detected inside the Morashes' unit in the South Berkeley fourplex despite multiple experts looking for the source, and the typical sources of carbon monoxide leaks, including heaters, stovetops, and the cars in the driveway, were not found to have dangerous levels of the "colorless, odorless gas," the San Francisco Chronicle reports.
Early reports pegged a laser cutter and 3D printer in the home as possible culprits, but officials ruled them out after learning that the printer wasn't powered on at the time and the power strip the laser cutter was plugged into was switched off. (3D Printing Industry even debunked the news pinning the blame on the 3D printer back in January.) Experts are calling the case "rare and odd," noting it's typically easy to pinpoint the origin of carbon monoxide in a case like this, and they add that the lack of answers is potentially a public health concern. Neighbors agree—though the unit where the Morashes lived has been red-tagged, the other three units in the building have been deemed safe after official inspections and the installation of carbon monoxide detectors near bedrooms. (A detector was located on the ground floor of the Morashes' unit, but not upstairs where they slept.) Click for more on the story. (Read more carbon monoxide stories.)