Three “severely decomposed” bodies of a California family were discovered in their home by police Wednesday morning in what is being investigated as a year-old murder-suicide.

Cops were conducting a welfare check on the family at their Irvine residence when they stumbled upon the decaying remains of a father, mother and their adult son, according to a press release.

The corpses had been decomposing for more than a year, the Irvine Police Department believed.

“Extended family members of the residents of the home reported to Canadian authorities they had been unable to reach the residents for over one year and were concerned,” police wrote.

“Responding officers entered the home and discovered three severely decomposed bodies inside that appeared to be adults.”

There were no signs of forced entry to the home and police found evidence of a “domestic-related incident that resulted in a murder-suicide.”