Courts have seen the number of sex offense cases involving juvenile offenders rise dramatically in recent years, an Associated Press review of national statistics found, and treatment professionals say the offenders are getting younger and the crimes more violent.

Some psychologists blame the increase in numbers — 40 percent over two decades —on a society saturated with sex and violence and the fact that many of the accused were themselves victims of adult sexual predators. Others say there aren't more children committing such crimes, simply more awareness, better reporting and a general hysteria about sex offenders.

"I don't think it's appropriate to suggest we have whole schools full of sexual predators ... but we're seeing more of it and more sexually aggressive acts," said Scott Poland, past president of the National Association of School Psychologists. "How do these kids even know about this? It's permeated throughout our society."

Robert Prentky, a psychologist and nationally renowned expert on sex offenders in Bridgewater, Mass., thinks the statistics are misleading.

"There aren't more kids, there are more laws," he said. "We now have fairly draconian laws with very harsh sanctions that apply to juveniles."

The number of children under 18 accused of forcible rape, violent and nonviolent sex offenses rose from 24,100 in 1985 to 33,800 in 2004, the AP's analysis found. Violent offenses include attempted rape and sexual assault, while nonviolent offenses including fondling, statutory rape and prostitution.

By comparison, rape and sexual assaults by adults decreased more than 56 percent from 1993 to 2004. Comparable statistics were unavailable before 1993.

The AP analyzed state and federal crime statistics, as well as independent research on juvenile sex offenders. Sources included the U.S. Department of Justice's Bureau of Justice Statistics; the National Center for Juvenile Justice, a Pennsylvania-based nonprofit that specializes in statistical and policy research; and The Safer Society Foundation Inc., a Vermont nonprofit that works to prevent sexual abuse.

Sharon Araji, an Alaska psychologist who took one of the first broad looks at the problem in her book "Sexually Aggressive Children," thinks the number of child-on-child sex crimes is actually even higher than the statistics indicate.

Only 28 percent of all violent sexual assaults are reported to police, according to a 1999 National Crime Victimization Survey. And cases of incest between siblings are widely thought to be underreported and may drive the numbers even higher, Araji says.

"The whole society is not yet up on this problem," Araji said. "These kids, on the extreme end, if nothing is done to catch them, they're going to become our adult offenders of tomorrow."

Studies show that one in two sex offenders began their sexually abusive behavior as juveniles.

The rise in juvenile sex offenders has spawned hundreds of new treatment facilities for children as young as 5.

In 2002, there were 937 programs in the U.S. treating adolescent offenders _ generally ages 12-17 _ up from 346 in 1986.

During the same period, the list of programs specifically aimed at children under 12 grew from zero to 410, according to The Safer Society Foundation.

However, Franklin Zimring, a juvenile justice expert at the University of California, Berkeley, thinks many children are unnecessarily treated as sex offenders. True pedophiles are extremely rare among young people, he says.

"As long as the public temperature is up, you're going to get more referrals from the courts for treatment," he said. "If you don't want to lock a kid up, treatment is a politically safe outcome."

Many experts agree that some amount of sexual exploration by young people is healthy, a line is crossed when force and violence are involved, they say.

Recent incidents include the cases of two 13-year-old boys in Omaha, Neb., who were accused in January of videotaping their assault of two 5-year-old girls and a 3-year-old boy, and of an 8-year-old Buffalo, N.Y., boy accused of assaulting a 6-year-old boy after he saw a prison rape scene in an R-rated movie.

In Alaska, lawyer Dennis Maloney calls it an epidemic.

His state has one of nation's highest per capita rates of youth sex offenders in treatment and one of the highest rates of treatment programs per capita. Others in the top seven are Hawaii, Idaho, Minnesota, Montana, New Hampshire and Vermont, according to the Safer Society Foundation.

Maloney represents the family of a 6-year-old boy raped by a fellow kindergartner. "He said 'Please, I'll be your best friend,'" the alleged victim said, according to a transcript of an interview with a police officer.

Experts say certain trends emerge among the cases of children charged with sex crimes against other children. Many — estimates range from 40 percent to 80 percent — were molested themselves, the Office of Juvenile Justice and Delinquency Prevention said in a 2001 report.

Psychologists prefer to refer to juveniles charged with sex crimes as "sexually aggressive children," rather than as sex offenders.

Psychologist Heather Bowlds, who runs a sex offender treatment program within California's Department of Juvenile Justice, says sexually aggressive children often have a skewed sense of sexuality in which force or violence becomes normal.

"Some kids see it as how you show affection, how you get your needs met," she said. "If you're a kid watching your father rape your mother ... if I feel like I want it, I can get it, no matter what."