MOSCOW, September 18. /ITAR-TASS/. Moody’s on Thursday placed on review for downgrade the Ba2 corporate family rating (CFR) and the Ba2-PD probability of default rating (PDR) of services conglomerate AFK Sistema and the Ba2 CFR and the Ba2-PD PDR of Bashneft, which is Sistema’s 74-percent subsidiary, the international ratings agency said in a statement.

The rating action came after news that Sistema chairman Vladimir Yevtushenkov was placed on September 16 under house arrest on suspicion of involvement in a money-laundering scheme with the assets of oil companies in the Urals Republic of Bashkortostan, which are now part of Bashneft oil producer controlled by the tycoon.

Earlier, Fitch Ratings put the ratings of AFK Sistema and its subsidiaries - mobile operator MTS, Bashneft and bank MTS Bank - on Rating Watch Negative, according to the ratings agency’s statement released Thursday.

The stocks of firms owned by Yevtushenkov plummeted on Wednesday on news of his arrest, with public companies integrated into Sistema losing over $5.5 billion in their market value.

If convicted, the Sistema chairman may be sentenced to seven years in prison. He has rejected all the accusations and insists on his innocence.