The Berkeley Police Department believe Roger and Valerie Morash's death was a tragic accident.
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It took some time to determine the cause because officials had to process autopsy findings, toxicology reports, necropsy, and other tests.
During the course of the investigation Berkeley police investigators collected various items within the apartment to test for toxins. The State of California Public Health Department determined none were present. Necropsy examinations were performed on the couple's two cats and the results determined the cause of death was carbon monoxide.
Investigators are still trying to identify the specific source of the carbon monoxide.
Out of an abundance of caution, investigators reached out to the landlord to coordinate tests and inspections for Unit 4. In order to conduct the tests in the safest manner possible, investigators wanted to arrange for the building to be unoccupied.
Investigators did not order anyone to evacuate their apartments. The proposed tests have been cancelled while the Department works through the residents' concerns.
Investigators are focused on trying to determine the source of the carbon monoxide in order to provide peace of mind to the families and residents of the building.
Neighbors were upset over what they say was a shortage of information before the confirmation.
Two weeks after that couple was found dead, there were still no answers and no updates on what caused their deaths. "We're just all up in the air about this," neighbor Marie Nadeau said. The air is what has her worried. Nearly two weeks after her neighbors and their two cats were found dead in their apartment, there's still no official word on how they died.
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Nadeau's carbon monoxide detector was working. In fact, in the hours after the bodies were found, police asked PG&E to come test for the poisonous gas, most often released from faulty furnaces.
They say they found nothing and gave the all-clear. But a week later, Nadeau says the landlord wanted to test again. "They said you didn't have to be out of the building but we strongly advise it, no other information," she said.
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Nadeau booked a hotel room for her and her cat. Then she got an email. "This email is to advise that the future testing requested by the Berkeley Police Department scheduled for Friday, February 3 at 6 p.m. will not go forward," she said.
Postponed indefinitely, on less than a day's notice. "I can't cancel my room without paying the full price of the room, $213 bucks," she said.
The neighbors were left in limbo. Nadeau was wondering whether her gas wall heater is even safe to use. "It's been cold and while my inclination is not to run it, I have to confess I did," she said.
For now, she'll stay in her home and as for that hotel room, "I don't think I should have to pay that. I think I should just take it out of my rent."