A man, a woman and a family dog are dead and police are investigating the deaths as accidental.
Police responded to a home on Sleeping Giant Drive in Hamden on Tuesday morning and found a car running in the garage.
The cause of death appears to be carbon monoxide poisoning, according to several reports. The woman died on the way to the hospital, officials said.
Neighbors said the two victims were a couple in their 60s.
More information will be posted once it becomes available.