Police in the Thai resort town of Pattaya have charged the renowned Russian pianist Mikhail Pletnev with raping a boy.
The musician, who conducts the Russian National Orchestra (RNO), was bailed and later received permission to leave Thailand temporarily.
Mr Pletnev, who owns homes and businesses in Thailand, called the case a "misunderstanding".
His orchestra is due to begin a tour of Europe and the US this week.
A senior police officer told the BBC that Mr Pletnev had been charged with raping a boy and that photographs had been collected from one of his properties.
Police are making other checks after a Thai tenant in one property he owns was arrested on suspicion of paedophilia.
The tenant was among several Thais being questioned over alleged involvement in a child sex ring. They reportedly informed on Mr Pletnev.
"We received a tip-off from a detained Thai man who is involved in a prostitution ring," said Lt Col Omsin Sukkanka, from the children's and women's protection centre of the Pattaya police.
"And we received more information from the child's parents, the child himself and other witnesses."
The head of the consular department of the Russian embassy in Thailand, Andrey Dvornikov, said Mr Pletnev maintained he was innocent.
"The police have made accusations," he said. "But allow me to repeat that Mikhail Pletnev denies all these charges."
Mr Pletnev was first questioned by police on Monday at a restaurant he co-owns in Pattaya, a resort and nightlife town east of Bangkok.
He co-operated with a search of his home.
He then reportedly promised that he would not flee the country because of the case against him.
"This whole thing is a misunderstanding," he told The Associated Press.
Mr Pletnev is an internationally famous musician - a virtuoso pianist, composer and conductor - and a friend of former Soviet President Mikhail Gorbachev.
He won a Grammy in 2005 for an arrangement of Prokofiev's Cinderella.
He holds the highest award given to artists in Russia, that of People's Artist, and is a member of the president's advisory committee on culture.
He has also performed as a guest conductor of the Bangkok Symphony Orchestra.
The RNO is due to begin its summer tour in Macedonia on 12 July before moving to California a few days later, then returning to Europe in August for concerts in London and other cities.
A Thai court has allowed Mr Pletnev to leave the country provided he returns by 18 July for his next court appearance, Mr Dvornikov said.
Denying he would try to flee the country, Mr Pletnev told AP: "I would jump from the 26th floor [of a building] tomorrow, if I could believe those news reports."