SAN FRANCISCO, California (CNN) -- Police arrested a third suspect in the case of an emaciated, nearly naked teenager who is said to have escaped his captors and wandered into a gym with a shackle on his ankle, authorities said Wednesday.
Police say a bruised, emaciated teen boy wandered to this gym after being held in a home in Tracy, California.
Police arrested Caren Ramirez, 43, after following up on a tip that she was living in Berkeley, a suburb of Oakland, California, said Matt Robinson, a police spokesman in Tracy, where the alleged crime took place.
Ramirez was being taken Wednesday to Tracy, about 70 miles east of San Francisco.
Ramirez is believed to be the aunt of the 17-year-old boy, who walked into a gym in Tracy on Monday. Two other suspects were in custody in the case.
The teen was dressed in boxers, his body was bruised, and his shackled ankle was bloody, Robinson said earlier. Watch how the strange case unfolded »
Also in custody are Kelly Layne Lau, 30, and her husband, Michael Luther Schumacher, 34. They are being held on charges of kidnapping, torture, false imprisonment, child endangerment and corporal injury to a child, Robinson said.
Police are trying to ascertain the connection between the aunt and the other two suspects.
Lea Leonardo, assistant gym manager, said the teen came into the fitness center and begged her to hide him.
"He was very dirty. He looked very young, very skinny and was wearing nothing but men's oversized boxers," Leonardo told CNN's Nancy Grace. "He was terrified."
Robinson said the teen had been held at the home of the suspects, about 500 feet from the fitness center. It was unclear how long the teen had been held, he said.
"The victim said he was held against his will," Robinson told reporters Tuesday.
"When you have a 17-year-old boy showing up with a bloody ankle from having a chain wrapped around it -- it was one of those things where officers put one and one together."
Four other children belonging to Schumacher and Lau, ages 1, 3, 7 and 9, were at the home. All were taken by the San Joaquin County Child Protective Services and showed no signs of abuse, Robinson said.
At some point earlier, social workers took the teen from his parents, and he ended up living with his aunt. Later, the aunt was charged with felony abuse, and the teen was put in a foster home, Robinson said.
The teen escaped the foster home and somehow reunited with the aunt, Robinson said.
The teen, whose name was not released, was in stable condition at a hospital, suffering from bruising, cuts and malnutrition, Robinson said.
Lau and Schumacher are being held with bail set at $1.2 million each, according to the San Joaquin County sheriff's Web site. The two will be arraigned Thursday, Robinson said, but arraignment for Ramirez probably won't be scheduled until Monday.
CNN's Andrew Iden, Matthew Zarrell and Ellie Jostad contributed to this report.
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