A Russian investigator, taken off the investigation into alleged corruption on the part of President Yeltsin and his close associates, has now been removed from his post as head of the serious corruption section of the Russian State prosecutor's office. Just before that, he had told The Irish Times that 90 per cent of the reports linking Mr Yeltsin, his family and allies to corrupt practices in Switzerland were true.

Georgy Timofeyevich Chuglazov was due to go to Switzerland on behalf of the Russian prosecutor's office this week but was taken off the case and had his phone cut off. Speaking to The Irish Times in Moscow, he said he was approached by his superiors, who said his concentration on the case involving "the Family", as the Yeltsin entourage is known, was distracting him from his other duties as head of the department for investigating serious corruption.

"My attention may have been drawn away from other things, but I ask you, which is more important? In my view it is that particular investigation," Mr Chuglazov said. Asked what details of the allegations could be included in the "10 per cent untrue" category he said: "I can't tell you that. I don't want to interfere with the investigation. I am not a dissident. I still have to work here."

Attempts yesterday to contact Mr Chuglazov at his Moscow office after he had spoken to The Irish Times were met with the reply: "He does not work here any more. He has another job."

It was learned that Mr Chuglazov had been made a special assistant to Russia's prosecutor general, Mr Vladimir Ustinov. His new post is ostensibly a promotion but it moves him even further away from the investigation into Mr Yeltsin and his associates.

The affair began with an investigation by Switzerland's prosecutor general, Carla del Ponte, into Russian involvement with Swiss companies and ended with disclosures in the Italian newspaper Corriere della Sera accusing Mr Yeltsin and close political associates of accepting bribes of up to $1 million.

A key figure in the murky business is millionaire playboy and businessman Behxet Pacolli, a Kosovo Albanian from near Pristina who runs a construction company called Mabetex out of a plush office block in Lugano, Switzerland.

Pacolli, according to Corriere della Sera, supplied credit cards to Mr Yeltsin and his two daughters, Tatyana Dyachenko and Yelena Okulova, and gave kickbacks to the administrator of the Moscow Kremlin in return for a contract to reconstruct the government offices there.

Known for appearing in public with extremely beautiful women, Pacolli, in an interview on Russia's Vremya TV News, described the credit card allegations as fantasy but admitted that he had been interviewed on the subject by Ms del Ponte.

Ms del Ponte, who is shortly due to take over as head of the United Nations Yugoslav war crimes commission, is an internationally-respected investigating lawyer. The investigation, which she began in 1997, has been linked to one of the most bizarre series of events in Russia's recent history.

It involves sex, lies, videotape, bribery and corruption, perhaps murder, and may even have led to the sacking of Russia's most popular politician, Mr Yevgeny Primakov, from his post as prime minister, the second most powerful job in the Russian Federation.

Russia's prosecutor general, Yuri Skuratov, co-operated with the Swiss authorities in investigating the allegations. President Yeltsin asked for his head, but Skuratov fought back and got the support of the Federation Council. Then Russian TV showed a videotape of a man who looked like Skuratov in bed with two prostitutes. Skuratov lost his job.

Mr Primakov, who backed Skuratov's investigation, was also sacked as prime minister by Mr Yeltsin, ostensibly for not fixing Russia's economy during his short term in office. Most observers felt he lost his job because of Mr Yeltsin's jealousy of his growing popularity, but many felt it was linked to Skuratov's investigation.

The big break for Ms del Ponte came in 1998 when she was contacted, according to Corriere della Sera, by an elegant young banker called Felipe Turover, of mixed Spanish and Russian origin. Turover worked for the Banca del Gottardo in Switzerland. His job was to recover credits for bank clients who were owed money by Russian companies. Both Turover and the bank took percentages of the reclaimed money but the customers were happy to get anything at all.

Turover claimed to del Ponte that a colleague who was jealous of his success was trying to blackmail him. To get at the alleged blackmailer he was prepared to hand over a list of accounts in the Banca del Gottardo which were accessed by Kremlin officials.

Carla del Ponte referred Turover to Yuri Skuratov in Moscow. Turover is reported to have handed over a list of 23 names to the Russian prosecutor, chief among them being that of Pavel Borodin, the man in charge of administering the Kremlin, its buildings and its employees. The money in the Banca del Gottardo accounts came, according to Turover, from Mabetex, a company owned by Bahxet Pacolli. Mabetex, he alleged, had also transferred money to Mercata Trading of Geneva, a company headed by Viktor Stolpovskikh, a close associate of former Russian prime minister Viktor Chernomyrdin.

Corriere della Sera also reports that Pacolli told Carla del Ponte that a transfer of $1 million from his private account to a bank in Budapest was for expenses for President Yeltsin. On Friday, January 22nd, 1999, according to the Italian report, Ms del Ponte discovered a filing cabinet in Pacolli's office containing references to credit card transactions in the names of B. N. Yeltsin, Yelena B. Okulova, Tatyana B. Dyachenko and A. Korzhakov.

Yelena Borisovna Okulova is Mr Yeltsin's elder daughter. Tatyana Borisovna Dyachenko is his younger daughter. Alexander Korzhakov, a former KGB general who headed Mr Yeltsin's Kremlin security, claimed this week he had been asked to kill Moscow Mayor Yuri Luzhkov, a political rival of Mr Yeltsin's group. The man who asked him, he said, was Boris Berezovsky, a business and political associate of Tatyana Dyachenko.

Corriere della Sera reported that at a meeting in Lugano Pacolli handed del Ponte details of credit card transactions which showed that Tatyana Dyachenko had spent the equivalent of £8,000 sterling in a single day's shopping, but that there were few transactions on the President's card.

On Russian TV this week, Pacolli gave his account of the story. Ms del Ponte had asked him about the credit cards. "I did not understand what she meant. I took out my own credit cards. `Is that what you want?' I asked her. She started laughing and said: `stop that."'