Missing US teen's case linked to incestuous child sex ring

By most accounts, 19-year-old Brittney Wood was with her uncle Donnie Holland on the night of May 30, 2012, the last time anyone saw her in the US state of Alabama.

Holland - under investigation for horrific sex crimes at the time - took his own life within days of the disappearance.

The investigation that followed has unravelled what authorities describe as a dark, twisted tale of perversion in the working-class neighbourhoods and backwoods of coastal Alabama.

Eight of Woods' adult relatives and three family friends face dozens of charges as the alleged members of an incestuous ring that authorities say shared children for group sex.

Prosecutors say Holland was the leader of what has been described as the largest sex ring ever uncovered in Alabama. Wood was a victim and likely key witness.

"Brittney could have been huge," said prosecutor Teresa Heinz.

"She could have corroborated so many things."

Wood is presumed dead, but authorities haven't found a trace of her and no one is charged in her disappearance.

Even without Wood to testify, two of her uncles and an older brother already have pleaded guilty to sex charges, and jurors this month convicted a friend of Holland's of multiple sex charges in the first trial.

Others - including the missing teen's mother, Chessie Wood, and two aunts - await trial.

Chessie Wood denies committing any crime, but says some of her closest relatives are guilty of abusing children, including her daughter.

"There are innocent people in this and there are guilty people in this," Wood, 39, said in an interview.

"I don't know how the judicial system is going to figure it all out because they're not the sharpest tools in the shed."

Chessie Wood, accused of having sex with a young female relative, said she had no idea what was going on in the family until after her daughter's disappearance.

"The number one thing here is to find Brittney. The number two thing is to get all these sick (people) off the streets," she said.

Authorities are making plea-bargain offers and getting ready for more trials, but questions persist.

Perhaps most troubling, is why didn't child welfare workers pursue charges following what prosecutors describe as multiple complaints about sexual abuse within the family going back at least six years?

The case is so big officials don't know exactly how many kids inside and outside the family might have been victimised; estimates range from 11 to 16 children who were as young as three or four when they were first molested or made to watch adult relatives during drug-fuelled orgies.

The children of the suspects have all been placed in foster care or with relatives who weren't involved in the crimes.

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