The police in California rescued 13 malnourished siblings who were being held captive in a house in Perris, and have arrested their parents for torture, The New York Times reported.

The Riverside County Sheriff’s Office said they made the discovery after one of the children, a 17-year-old girl, escaped the house early on Sunday and used a mobile phone to call the police. Perris is 113 km east of Los Angeles.

The sheriff’s office has not yet released details on how long the children were held captive. However, they said their officers found the siblings, aged between 2 and 29, in a foul-smelling house.

They said some of the children were found shackled with chains and padlocks, and that at first sight, they did not realise seven of the 13 siblings were adults because they were that emaciated.

The police said they first thought the 17-year-old girl who escaped was 10.

The parents, David Allen Turpin, 57, and Louise Anna Turpin, 49, were both arrested on nine counts each of torture and child endangerment. They were not able provide a “logical reason why their children were restrained in that manner”, the Sheriff’s Department said, according to AFP.

The police have set bail at $9 million each.

California records show David Turpin was registered as the principal of a private institution called Sandcastle Day School. The registered address, however, is the Turpins’ home.

The school opened in March 2011, and has just six students. The Turpins filed for bankruptcy the same year, The New York Times report said.

Between 2011 and 2016, a Facebook page ‘David-Louise Turpin’ had regular updates of pictures of the couple and the children. The latest set of photographs, uploaded in 2016, showed Louise Turpin in a white wedding gown, and her husband in a suit, exchanging wedding bands.

They are surrounded by the 13 siblings, all smiling.