Two children were found dead in a storage unit in northern California, police said on Monday.

KSBW reports the bodies were located in the city of Redding, where authorities were investigating the case of abuse against a third child.

The children were siblings, aged 3 and 5.

The third child, a 9-year-old girl, was found to have been severely abused and is currently in serious condition after undergoing surgery.

Tami Joy Huntsman, 39, and Gonzalo Curiel, 17, were arrested Monday on charges of felony child abuse, torture and mayhem. They will likely also face murder charges.

According to Plumas County News, the two suspects were a couple. They were discovered after a child welfare check led police to an apartment complex on Fremont Street in East Salinas. Eventually, they located a young girl locked in a vehicle on the corner of East Main and First streets.

After intensive questioning by law enforcement, Curiel revealed the location of the children's bodies.

Two other children, 12-year-old boy and girl twins, were reported to be at an East Quincy residence where Huntsman and Curiel were temporarily staying. The children were immediately placed in foster care.

Sheriff Greg Hagwood said the incident struck an emotional chord with everyone involved.

"This has shaken my staff to the core," Hagwood said. "That little girl had been subjected to the most unspeakable measure of torture for an extended period of time. This is child abuse, the likes of which we haven't experienced here (in Plumas County)."

The girl was said to suffering from severe injuries, including a broken shoulder and fingers, a dislocated jaw, and missing teeth, among other concerns.

Huntsman is allegedly the biological mother of the twins, and an aunt to the 9-year-old girl. Her relationship to the deceased children is unknown.

The two suspects are being held at Plumas County Jail on $1 million bail.