The old problem of bullying in schools has taken a modern twist in South Korea, where, until a recent crackdown, gangs were using the latest communications technology to form mini-crime syndicates among groups from several schools.

With names such as the Seoul Association, the syndicates, engaged in extortion, assault, robbery and prostitution in Seoul, the capital.

South Korea's National Police Agency stamped out the syndicates this year and cut down on bullying with a forceful nationwide campaign.

But experts on the subject say what happened in Seoul may represent the future of bullying, in the rest of the country and in other parts of the world.

In March, police, along with parents, teachers and prosecutors, launched a huge program to curb school violence, setting up 24-hour telephone hotlines, counselors for victims, special school police and an amnesty period for gang members who wanted to confess to petty crimes.

"We set up this program to teach the students of the dangers of these gangs. Our emphasis is on helping the victim, reforming the assailant and seeking criminal prosecution for those few who commit terrible crimes," said the police agency's Lee.

Police identified and disbanded three gang networks. The Seoul Association was the largest, with 307 members from 94 junior and senior high schools. The other two were organized among junior and senior high school students from two affluent areas of Seoul.

Lee said the groups set up their own Internet sites for organizing events, such as street brawls with other syndicates to see which group had the better fighters. Members used text messaging to communicate in class and to members in nearby schools.

"If we had let them alone, they would have gone nationwide," said Lee Kumhyoung, director of the women and juvenile affairs division of the National Police Agency, adding that police believed that the syndicates had been extinguished.

Reflecting social hierarchies in South Korea's Confucian society, the syndicates were highly ordered based on seniority. Web sites also listed a pecking order of gang members based on fighting skill.

This top-down structure mirrors life in South Korea's pressurized schools, which have a rigid system of discipline and structured relationships where juniors must obey their seniors. Seniors can often act with impunity toward juniors, which helps bullying become a part of school life, experts say.

Add to this young people's access to high-tech communications devices here in the world's most wired country and it is no surprise that gangs use their phones to branch out and to organize extortion or other rackets that prey on the weak, experts said.

The groups put the squeeze on students to raise money for senior syndicate members so they could go out on expensive dates. The Seoul Association used its organizational skills to host seven sexually charged dance shows, where they auctioned off dating partners.

The groups committed mostly petty crimes, but some also engaged in prostitution and rape, members said. The gangs comprised elite students as well as class bullies, with girls forming a large part of the syndicates.

A 16-year-old high school student, who asked that she only be identified as Kim, was a part of the Songpa Association, which brought together boys and girls from an affluent area of Seoul.

"My seniors forced me to steal car stereos from parking lots in the middle to the night, and to bring girls around for their birthday parties so they could have fun," Kim said.

"Selling sex to top members was a way other leaders in the group could keep their control," she said.

Experts are worried that similar patterns of criminal activity could emerge in other parts of the world that have high population densities and tech-savvy students .

"What is going on now in South Korea could become the model in other parts of the world," said Shin Younghee, a criminal sociologist at Seoul's Hanyang University.

"Access to the Internet and sending SMS text messages by mobile phones are among the easiest and fastest ways to organize crime efficiently," she said. So far, other police forces have not worked with South Korea on this problem.

Although the crime syndicates may have been eradicated, gangs at individual schools still thrive, police say.

Police studies show that if a student joins a gang it is usually in junior high school. Among the gangs tracked nationwide, 54 percent are for boys and 46 percent for girls. Girls favor designer brand names for their groups.

"Criminal organizations will gain more power if they are connected under a big, central command," Shin said. "I think these junior and senior high school students understood this concept and used the tools at hand to seize on forming their syndicates."

Students in Seoul walked to school earlier this month under the watchful eye of a police patrol, necessitated by the rise of high school crime syndicates.