PHILADELPHIA — A Ukrainian hockey coach who allegedly had sexual contact with a teenage boy attending clinics in the United States frequently traveled with teens, transporting them from city to city for camps, according to court documents.

Ivan Pravilov is due in court later Friday for a detention hearing in Philadelphia. Prosecutors want Pravilov kept in custody because they believe he's a risk to flee overseas.

Pravilov was charged Tuesday with committing sex acts with a boy attending hockey clinics with him in the United States.

According to court documents, a 14-year-old boy told investigators he had sexual contact with Pravilov at an apartment in Philadelphia on Jan. 3. A second teen gave an identical account, according to the criminal complaint.

Pravilov was charged with transporting a minor to engage in sexual activity because he allegedly transported the boy from the home of a host family in Wilmington, Delaware.

The website for the coach's hockey school, Ivan Pravilov's Unique Hockey School, says it held a number of U.S. camps this summer.

New Jersey Devils forward Dainius Zubrus is one of his most famous proteges. Zubrus left his native Lithuania as a boy to play for Pravilov in Ukraine, and made the NHL by 18, according to his mother, Irene Zubriene. She and her son remain close to Pravilov, and the coach uses her Cherry Hill, New Jersey, home as a mailing address, she said.

Pravilov brings young hockey players to the U.S. for about a month at a time to train, play in tournaments and perhaps catch a college or NHL scout's eye, Zubriene said Friday. She and other families in the U.S. host the players. She said she has often had a dozen or more players stay in her downstairs living area, while Pravilov slept in an upstairs bedroom.

She does not believe the allegations and suspects they stem from lingering jealousy of Pravilov in the Ukraine.

"It's not true. It's not true," Zubriene, 60, who saw Pravilov last week, told The Associated Press during an interview Friday at her home. "He's a good man."

Pravilov's school had about a dozen players practicing at the same rink on Friday. A coach working with the players declined comment, saying he did not speak English.

Rink officials declined to discuss the matter on Friday, referring questions to a management company.

A woman who helped host families in the United States said she knew Pravilov well, having volunteered her time for the boys.

"It's still very hard to comprehend everything," said Denise Reid, a contact listed on Pravilov's website for another Philadelphia-area ice rink where he held camps. "We're devastated. We're worried for the boys."

A coach at Pravilov's school in Ukraine declined to give his name or to comment. The Interior Ministry, which oversees the Ukrainian branch of Interpol, had no comment.

An attorney for Pravilov didn't return messages seeking comment.

Associated Press writer Kathy Matheson contributed to this report.