A Bucks County publisher who started a foundation to aid survivors of a bloody 2004 hostage crisis at a North Ossetia school was arrested Tuesday for alleged involvement in a prostitution ring in Russia involving women and minors, authorities said yesterday.

Andrew Mogilyansky, 38, of Richboro, was charged in a complaint filed in U.S. District Court in Philadelphia. Girls as young as 13 from a St. Petersburg orphanage were among his alleged victims, the U.S. Attorney's Office said.

Mogilyansky, chairman and founder of the Bensalem-based International Foundation for Terror Act Victims, had raised money over the Internet to help survivors after armed rebels, demanding an end to hostilities in Chechnya, took more than 1,100 people hostage in September 2004.

After a three-day standoff with the rebels, Russian security forces stormed the school in the town of Beslan. At least 334 hostages were killed, including 186 children, and hundreds of people were wounded or reported missing.

Less than two weeks after the massacre, the New York Daily News reported that Mogilyansky had raised more than $650,000 for survivors. "Our goal is $10 million," Mogilyansky said then. "We will not touch a penny of personal donations. For every dollar we receive, we will deliver a dollar to the recipient."

But Mogilyansky, a dual citizen of Russia and the United States, was not just a legitimate businessman and philanthropist, authorities believe.

In fact, they said yesterday, he already had been running an Internet-based child-prostitution ring in Moscow when he was raising the aid money.

They said he traveled to Russia between December 2003 and January 2004 to engage in sex acts with girls in his St. Petersburg apartment as a way of introducing them into the child-prostitution ring.

With the help of Russian citizen Andrei Tarasov and three other Russians, authorities said, Mogilyansky created a Web site called "Berenika" that marketed the women and girls as prostitutes in Moscow between 2002 and 2004 - a business from which he allegedly profited.

"[He] took what little they had - their innocence and their dignity," said U.S. Attorney Laurie Magid. "Not only did he molest them for his own pleasure, but he treated these children as a commodity - useful, marketable, and ultimately disposable."

Mogilyansky's attorney, George Newman, declined to comment on details of the case. "We deny the allegations and look forward to contesting them in court," Newman said.

If found guilty of all charges, Mogilyansky faces a maximum of 120 years in prison and a $1 million fine, according to the complaint.

Mogilyansky had a net worth of $5.3 million in 2006, according to the criminal complaint. He also reported in 2006 that he was the chief executive officer of Ifex Global, a company that was valued at $10 million in 2004 and that distributes fire extinguishers and equipment; and a car-export business, the complaint says.

The Inquirer reported in 2004 that Mogilyansky had come to the United States in 1989 and graduated from Columbia University five years later.

The newspaper reported that the International Foundation for Terror Act Victims "was very modestly housed in a small Bucks County office where Mogilyansky publishes 'The Russian Yellow Pages' of Philadelphia, New Jersey, New York and the Baltimore-Washington area, and also a Russian language newspaper distributed in Philadelphia."

Yesterday, Magid said that Mogilyansky's alleged criminal ties extended to Russia itself. "He believed that if he went far enough away, he would avoid the interest of law enforcement," she said. "He was wrong. Very, very wrong."

Mogilyansky's alleged co-conspirators were arrested and convicted in Russia in 2004, the same year the prostitution Web site was shut down, authorities said.

Magid said the case was still under investigation and declined to comment on how Mogilyansky had obtained girls from the orphanage.

The U.S. Attorney's Office also filed a motion to detain Mogilyansky, citing that because of his substantial wealth and contacts in foreign countries, he has ample ability to flee the country.

The foundation's Web site, www.moscowhelp.org, lists Mogilyansky as chairman and founder, giving the foundation's mailing address as 959-A Bristol Pike, Bensalem.

Michael Ratner, a computer analyst in Tenafly, N.J., listed on the foundation's Web site as its vice president and trustee, said yesterday that Mogilyansky had "done a lot of good work."

"I have known him for over 20 years," Ratner said. "We went to high school together. "He's a very good person and has helped a lot of people."

U.S. Immigration and Customs Enforcement (ICE) worked with St. Petersburg police, the Russian Ministry of Internal Affairs, and the Investigative Committee of the General Prosecutor's Office of the Russian Federation to bring charges against Mogilyansky, the U.S. Attorney's Office said.