Updated at 5:25 p.m. ET: LOS ANGELES -- A scrawny Georgia teen who was discovered at a bus station told police his abusive stepfather gave him $200 and a list of homeless shelters before he was put on a bus to Los Angeles on this 18th birthday, authorities said Thursday.
Retired Los Angeles police Sgt. Joe Gonzalez was working security at a downtown bus station Sept. 11 when he spotted Mitch Comer, who stood just over 5 feet tall, weighed 87 pounds and looked much younger, the LAPD said in a news release Thursday.
The teen told Gonzalez his stepfather declared that he was now a man before putting him on a bus.
Paul Matthew Comer is seen in an undated photo provided by the Paulding County Sheriff's Office.
Investigators in Paulding County, Ga., planned to search at the home where authorities allege the teen was kept in such seclusion that his two younger sisters in the same house did not know what he looked like.
"The sisters haven't seen the brother in over two years," Paulding County sheriff's Cpl. Ashley Henson said. "They didn't even know what color his hair was."
Stepfather Paul Comer and mother Sheila Comer face charges of false imprisonment and cruelty to children, Paulding County jail records show. They were being held without bond.
Police described him as "pale" and "gaunt" and said they believed he was around 12 or 13 years old at first. Concerned about his age, they decided to investigate further.
Sheila Comer is seen in an undated photo provided by the Paulding County Sheriff's Office.
"The LAPD officer said his skin was translucent, that he was obviously malnourished," Los Angeles District Attorney Dick Donovan told WSB-TV in Atlanta.
The 18-year-old told authorities that he had suffered years of abuse. After removing him from school in the eighth grade, his stepfather shut him in a room, he said.
The youth was fed only small amounts of food and forced to hold a grueling disciplinary position for eight hours a day with the top of his head against a wall, his fingers interlaced behind his head, and his feet raised off the ground.
The teen told police he had two younger sisters still living at home, but he did not know his address. LAPD contacted local Paulding County, Georgia, sheriff's deputies, who tracked down his stepfather and mother and took them in for questioning.
The parents were subsequently arrested on child abuse and false imprisonment charges. Detectives also put the teen's younger sisters, aged 11 and 13, into protective custody with Paulding County Children's Services.
After staying in a Los Angeles board and care home, the 18-year-old flew to Georgia on Wednesday to help in the investigation and legal proceedings against his parents.
"I am greatly relieved and thankful that one of our retired officers brought this victim to our attention and started the process to uncover these heartbreaking circumstances," Police Chief Charlie Beck said in a statement.
Dion Walker and Mea Smith, who live near the family in Dallas, Ga., told the Atlanta Journal-Constitution their children had played with the teen's sisters.
"Maybe, when the young girls would stare at us, were they trying to say something?" Walker said according to the Journal-Constitution. "Should we have noticed?"
Monica Moore, an investigator with the Paulding County district attorney's office, accompanied the 18-year-old home from California and described him to WSB-TV as small and very timid, but exceedingly polite.
"I made sure that he knew that ... once he came here he had a lot of people here helping," she told WSB-TV.
Donovan told the station his office struggled to find an agency willing to take in the teen because he is legally an adult, but a local family agreed to house him.
NBC News's Sevil Omer and The Associated Press contributed to this report.
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