Another allegation of sexual abuse emerged Thursday against kidnapping suspect Phillip Garrido, when Antioch police disclosed he was arrested nearly 40 years ago on suspicion of drugging and raping a 14-year-old girl.

Garrido was accused of sexually assaulted the girl at an Antioch motel in April 1972 after giving her barbiturates, Antioch police Lt. Leonard Orman said.

Garrido was set to be prosecuted in the case but the charges were dropped when the girl refused to testify, Orman said.

The girl and a friend met Garrido, then 21, and another man near the public library and joined them in a car, where they were given drugs, he said.

Details on the case were spotty because so much time had passed.

However, authorities recently reinterviewed the girl and were able to piece together that she awoke at the motel and was raped repeatedly before her parents found her, Orman said.

It was the third sexual assault linked to Garrido by authorities.

Garrido, 58, and his wife, 54-year-old Nancy Garrido, pleaded not guilty to 29 counts of kidnapping, rape and false imprisonment in the disappearance of Jaycee Dugard 18 years ago.

Police say the Garridos held Dugard captive in a backyard encampment of tents and sheds in Antioch, and Garrido fathered two children with Dugard.

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He was previously convicted in the 1976 kidnapping of a casino worker in Reno, Nev., who said Garrido raped her in a storage locker before police found them. He spent about 11 years in federal prison and was paroled in 1988. Dugard was abducted in 1991 near her South Lake Tahoe home.

Earlier Thursday, Jaycee Dugard's aunt read a brief statement to reporters saying her niece remembers her family and is enjoying getting to know her younger sister, who was a baby when Dugard was kidnapped.

Tina Dugard spoke to reporters at the FBI's Los Angeles office, describing her niece's reunion with her mother and sister.

"The smile on my sister's face was as wide as the sea. Her oldest daughter is finally home," Tina Dugard said.

Tina Dugard said her niece's daughters appeared to be bright and educated, even though they did not attend school.

"Jaycee did a truly amazing job with the limited resources and education that she herself had, and we are so proud of her," Dugard said.

The family's location has been a closely guarded secret since the 29-year-old woman reappeared last week. She was 11 when she was allegedly kidnapped.

Tina Dugard said the family has been spending time in a secluded place, reconnecting and getting to know each other again.

"Not only have we laughed and cried together, but we've spent time sitting quietly, taking pleasure in each other's company," Dugard said.

Tina Dugard took no questions from reporters and did not comment on the investigation into her niece's abduction. A spokeswoman for the Dugard family, Erika Price Schulte, said they would have no further public comment for now.