Man wakes up from surgery after stabbing his wife and ’spontaneously’ admits he killed his mom, police said

A Northern California man woke up from surgery after stabbing his wife and himself — then immediately confessed to having killed his mother at her home.

Officers with the Vallejo Police Department responded Saturday morning to an area inside Kaiser Permanente hospital , where 63-year-old Frank James McMillan and his wife were each being treated for "at least one stab wound," according to a press release issued by the VPD. Both were in critical condition, police said.

"Following McMillan's surgery, he spontaneously confessed to killing his biological mother at a residence on the 100 block of Campbell Avenue," the press release stated.

McMillan was visiting his wife, a patient at the hospital, when he stabbed her before turning the knife on himself, according to local Fox affiliate KTVU .

Police later showed up at McMillan's mother's home and forced their way inside, discovering the 80-year-old deceased. (Her name has not been released, pending family notification, according to the VPD. The Independent is withholding her name until it has been made public.)

A review of public records show McMillan and wife Mika Wilson both resided at the same address. They are each expected to survive their injuries.

McMillan was arrested and charged with attempted murder and murder , and will be jailed once he is "medically cleared for incarceration," the VPD release says.

The circumstances of the murder and any motive remain unclear.

The killing marks the 21st murder year-to-date in Vallejo, a Bay Area city of 122,000 people.

A spokesman for the Vallejo PD did not respond on Monday to a request for further information.