Officer Dave Pubins told CNN police were approaching Thursday's discovery of the bodies of two adults and two children in a Scottsdale home as a criminal act contained within the home and not involving anyone else.
"It's a tragic event," Pubins said. "It appears to be a murder-suicide. There are, at this point, we don't believe any outstanding suspects. We do believe that the scene is contained entirely inside of the home."
Mark Clark, another police spokesman, said a weapon and a note were also found in the rented home. Additional details regarding the discovered items were not provided.
The identities of the four victims, as well as a potential motive for the suspected multiple murder and suicide, were not reported.
Neighbors said a couple lived in the Scottsdale home with two sons, ages 5 and 10.
"They seemed to be very normal people, other than being quiet, no explanation really," neighbor Wayne Lehsten told CNN. He said the four never participated in neighborhood activities like block parties.