The horrifying discovery was made after a 17-year-old girl escaped the house in Perris, about 113 kilometres east of Los Angeles.
Using a mobile phone she'd found in the house, she called police, directing them to the home where her brothers and sisters were being held captive.
'Deputies located what they believed to be 12 children inside the house, but were shocked to discover that seven of them were actually adults,' the Riverside County Sheriff's Office said in a statement.
'The victims appeared to be malnourished and very dirty.'
Terrifyingly, several children were shackled to their beds with chains in 'dark and foul-smelling surroundings'.
'The parents were unable to immediately provide a logical reason why their children were restrained in that manner,' authorities said in the statement.
Their parents, David Allen Turpin, 57, and Louise Anna Turpin, 49, were arrested and each charged with nine counts of torture and 10 counts of child endangerment.
Their kids have all been transported to hospital.