Authorities arrived at the home to find several children shackled to beds with chains and padlocks, "in dark and foul-smelling" conditions, the Riverside County Sheriff's Department said in a news release.
The parents, David Allen Turpin, 57, and Louise Anna Turpin, 49, have been arrested on charges of torture and child endangerment. Their bail is set at $9 million each. They were "unable to immediately provide a logical reason" why their children were shackled and chained, authorities said.
Sheriff deputies were "shocked" to discover that seven of the "children" in the home were actually adults, according to the news release. The ages of the 13 victims ranged from 2 to 29. They appeared malnourished and dirty, and told authorities they were starving.
The girl who escaped managed to call police on a cellphone she found in the home. "She appeared to be only 10 years old and slightly emaciated," the sheriff's department said in their news release.
Authorities interviewed the children and provided them with food and drink. The six minors were taken to a hospital and admitted for treatment, the sheriff's department said. The seven older children were taken to a different medical center and also admitted for treatment.
According to public records, the couple own the home and have lived there since 2010. They previously lived in Texas for many years, and have twice declared bankruptcy.
One of their bankruptcy lawyers, Nancy Trahan, said in a phone interview Monday evening that she met with the couple about four or five times in 2011, but hasn't seen them since then. She described the couple as "just very normal."
"They seemed like very nice people," Trahan said. "They spoke often and fondly of their children."
She did not recall hearing about a school run from their home.
The couple's neighborhood is a new development of ranch-style homes located about 70 miles east of Los Angeles.
Kimberly Milligan, 50, who lives across the street, told the Los Angeles Times she only occasionally saw the children leave the home to get into a car with their parents.
The children were very pale, Milligan said. She frequently wondered why the many children never came outside to play.
"I thought the kids were home-schooled," she told the Times. "You know something is off, but you don't want to think bad of people."
David Turpin's parents, James and Betty Turpin of West Virginia, told ABC News they are "surprised and shocked" at the allegations. They said their grandchildren are home-schooled. They said they hadn't seen their son and daughter-in-law in four or five years.
Photos on a Facebook page that appeared to be created by the parents showed the couple at Disneyland with the children wearing matching shirts. Several photos appeared to be taken at a wedding ceremony. The parents posed in bride and groom attire, surrounded by 10 female children smiling for the camera in matching purple plaid dresses and white shoes. Three male children stood behind them wearing suits.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
Election Results for Lok Sabha Election 2019 will be out on May 23. Get the latest election news and live updates on ndtv.com/elections. Catch all the action on NDTV Live. Like us on Facebook or follow us on Twitter and Instagram for news updates from each of the 543 parliamentary seats for the election 2019