Two parents and their two children have been shot dead as police say they are not treating the case as murder-suicide.
Three dogs were also found shot dead in the home in Romeoville, a village around 26 miles from Chicago in the US state of Illinois, shortly after 8.43pm local time on Sunday (2.43am UK time on Monday).
Police found the bodies on Sunday night after a family member asked police for a “wellbeing check” because one of those who died didn’t show up for work that day.
Romeoville Police Department’s deputy chief Chris Burne said: “We don’t believe the offender is among the victims right now.
“It is not a murder-suicide.”
The parents have been identified as Alberto Rolon and Zoralda Bartolomei, the deputy chief said.
He added it wasn’t clear if they were married but they were the parents of the two child victims.
The children have not been identified and Mr Burne has declined to reveal their ages or genders.
He added that the ongoing investigation was “sensitive” in nature.
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Mr Burne said the motive is unclear but he does not believe the public is at risk.
He added that there’s no active police search for any suspected assailants near the home.