MOSCOW (AP) — A Moscow court has rejected an appeal by a prominent U.S. foreign investment manager and ordered him to remain in jail for at least the next month-and-a-half in connection with an embezzlement probe.

The Moscow City Court’s decision Thursday to keep Michael Calvey behind bars until April 13 comes despite numerous statements from prominent members of the Russian investment community who vouched in court on his behalf.

Calvey, who co-founded private equity firm Baring Vostok in 1994, was detained along with five others in Moscow on suspicion they embezzled 2.5 billion rubles ( million) from Vostochny Bank, in which Baring Vostok has a controlling stake.

The veteran American investor denies the charges and maintains that they spring from a business dispute between the bank’s shareholders.