A 13-year-old known as "Mr. Pimp" around his Reston middle school was convicted yesterday of trying to organize fellow students into a sex-for-hire ring.

The youth, a seventh-grader at Langston Hughes Middle School, told a Fairfax County police officer that a 12-year-old Reston girl also charged in the case recruited other girls to pay $10 to have sex with boys, according to testimony at the trial in Fairfax Juvenile and Domestic Relations Court.

Police and prosecutors said there was no evidence that any sexual acts took place.

Judge Michael Cassidy ordered the youth, who appeared in court with his parents, to remain at the youth detention center until his sentencing April 20. His mother cried quietly as he was led away in handcuffs.

The youth could be sentenced to remain at the detention center until he is 21.

According to testimony from police and children involved in the case, the 12-year-old girl allegedly forced seven other girls to pay $5 to $10 to have sex with boys at Reston Town Center, threatening them with physical harm if they refused. About five boys were recruited and told that if they paid $20, they could have sex with more than one girl, witnesses said.

Another 12-year-old girl at the school testified that she paid the $10 because "I heard I was going to get beat up." A 13-year-old girl said she did not want to be a prostitute but felt threatened and paid the money anyway.

"I asked him what will happen if I don't pay," the girl testified. "He said, If you don't, you will find out.' "

Fairfax police officer Gary Bailey, who is stationed at Langston Hughes and uncovered the scheme, said the youth told him he had made $75, part of which he used to buy three Eddie Bauer T-shirts from the Reston Town Center.

"He said he had ho's {prostitutes} and he was a pimp and that they would pay him money," Bailey said. "The girls would have sex, and they had to pay him a percentage of any money they made. I thought it was a joke."

Bailey said the youth also said that the 12-year-old girl charged in the case -- whom the youth called "my main ho" -- gave him $15, his proceeds from a $75 payment she allegedly told him she received for having a sexual encounter with a boy.

"He said he instructed {the 12-year-old girl} to develop a list with all his ho's and check off who had paid and who had not," Bailey said.

The 13-year-old was originally charged with two counts of "receiving money for soliciting other juveniles to perform sexual acts," but the judge dismissed one count and amended the second to attempted solicitation.

The youth said the girls told him they wanted him to sign a contract in which he would agree to protect them at all costs. But the youth said he refused out of concern that he would be blamed if the prostitution ring was exposed, Bailey said.

The youth's attorney, John A. Keats, said that he considered the judge's decision a partial victory and that the notion of a prostitution ring was a "fantasy."

"I think these kids watch too much television," Keats said.

Kitty Porterfield, Fairfax schools spokeswoman, said the case should send a message to parents and the community.

"We have to be continually vigilant with our children, and the schools are making every effort to do that," she said. "We are all stunned that children this young had knowledge of these kinds of behaviors, chose to mimic them and felt that this was a cool thing to do."