Police say three people have been shot and killed and another critically wounded in what appears to be a murder-suicide at a home in Northern California.

Modesto police spokeswoman Heather Graves says officers responding to a 911 call found two male victims and one female victim dead inside the house. They found a female victim alive, who was taken to a hospital in critical condition.

Graves says the initial investigation shows one of the male victims shot the others, then shot himself.

Police have not released the names or relationships between the four.

Modesto is a city of 200,000 people about 70 miles southeast of Sacramento.