JACKSON, Mississippi (CNN) -- Girls as young as 13 say they were shackled for weeks at a time in Mississippi.

A Texas teen was allegedly offered birthday cake in exchange for sex.

A guard drove his knee into the neck of a frail suicidal Ohio boy after the youth was wrestled to the ground and held down by other guards who stripped him and covered his face with a smock, a state report said.

More than two dozen girls at an Indiana lock-up describe "networking" -- their term for sneaking into each other's cells to have sex, with no interference from guards.

This is a glimpse into what America's juvenile jails look like, according to lawsuits, criminal cases and experts who have spent years delving into what they call a broken system.

"It's a nationwide crisis that has been going on for years, one the public has never been told the extent of," said psychiatric social worker Jerome Miller, the co-founder of the National Center on Institutions and Alternatives, who has evaluated and helped reform juvenile jails for more than three decades.

This summer, Mississippi plans to close Columbia Training School, a juvenile facility that houses mostly minor offenders. They are often runaways from abusive homes.

Erica was 16 when she was sentenced to Columbia after running away, a probation violation of an earlier marijuana conviction.

She admits she was a girl quick to sass her parents, full of anger about the death of a relative that happened around the same time Katrina wrecked her family's Bay St. Louis, Mississippi, home.

Nervously touching a sparkly barrette in her red hair, she cries as she describes how guards forced her legs into tight metal shackles. She said she was cuffed and chained when she ate and used the bathroom -- and was even forced to play soccer that way against other girls.

Guards called her "Chain Gang," she said.

"I will always remember them things around my ankles, the way they cut into me," she said, pulling up her pant leg to show slash-mark scars on her ankles and heels. "They made you feel like you were nothing." Watch teen explain suicide attempt was cry for help »

Represented by attorneys with the Southern Poverty Law Center, Erica and nine other girls housed at Columbia are suing the state, claiming they endured a range of sexual and physical abuse, including shackling. Don Desper, a licensed therapist and former employee at Columbia who opposed the practice, told CNN it was used to prevent the teens from escaping.

In a handwritten affidavit, a 15-year-old girl described a male guard molesting her. She wrote: "He came inside my cell half way half of his body and he started touching me and he tryed (sic) to kiss me and then he left he came back with my snack in his hand and he opened my cell again and he started grabbing me around my waist and he tryed (sic) to stick his hands in my pants and I started crying."

When the lawsuit was filed in 2007, a U.S. Justice Department monitor was making periodic inspections at Columbia as part of a 2005 settlement with Mississippi in a previous case. The Justice investigation that led to that settlement found Columbia youths were hog-tied, forced to strip and eat their own vomit and were held in isolation in what was called the "Dark Room," a windowless room with a hole in the floor used as a toilet. Read the Justice Department report that describes girls being shackled to poles

Hundreds of youths have allegedly suffered similar abuse at juvenile detention centers across the United States, according to experts interviewed by CNN and court records checked for this story.

The U.S. Justice Department has sued nine states and two territories alleging abuse, inadequate mental and medical care and potentially dangerous methods like the use of restraints. The department doesn't have the power to shut down facilities -- states do -- but through litigation it can force a state to improve its detention centers and protect the civil rights of jailed youths.

Another facility under Justice scrutiny is Oakley Training School near Jackson, Mississippi, which was sued by the department at the same time as Columbia. Gov. Haley Barbour recently announced Columbia's inmates would be transferred this summer to Oakley when Columbia is closed.

But the Justice Department said Oakley has satisfied barely a fraction of requirements the department set for it years ago. According to a March 2008 Justice report, there is an "enormous amount of work" needed to make Oakley a safe and productive place to rehabilitate troubled teens.

Barbour would not respond to questions for this report. The Mississippi Department of Human Services, which runs Columbia and Oakley, refused to answer most of a CNN public records request citing pending litigation and also declined to be interviewed.

The U.S. Justice Department could not talk specifically about ongoing cases, but Lisa Krigsten, civil rights division principal deputy assistant attorney general, noted the department is going after double the number of juvenile jails for civil rights violations during the Bush administration than in any previous administration.

"We take this seriously and are committed to protecting the vulnerable children who are in these places," she said.

A CNN check of other juvenile facilities shows that, despite years of court wrangling, serious problems persist.

In Ohio, a dozen employees at the Scioto Juvenile Correctional Facility have been indicted since 2003 on charges relating to physical and sexual abuse of youth, according to a May 2007 Justice report. Five were convicted of various charges, including sexual battery and assault; six cases were dismissed and a jury found one employee not guilty.

In January, a state-hired consultant blamed a "culture of violence" in Ohio's juvenile jails for numerous abuses. The expert's report details examples of "egregious use of force" by guards and included a video he viewed of a 2007 incident in which a "frail" boy who was threatening to harm himself was restrained by guards.

The boy was wrestled to the ground, cuffed and stripped, with one guard seen putting his full body weight on the boy's back while driving his knee into the boy's neck.

A so-called "Suicide Smock" was placed "over his airways," the report said. "The youth actually screams that he can't breathe."