BOSTON (Reuters) - Fremont General Corp FMNT.PK, a U.S. financial services holding company, said on Wednesday it had filed for bankruptcy protection in order to facilitate the sale of assets of its thrift unit.

Fremont, said in a statement that regulators had approved CapitalSource Inc's (CSE.N: Quote, Profile, Research) purchase of a substantial portion of the assets of Fremont's wholly-owned subsidiary, Fremont Investment & Loan, and the assumption of all of its deposits. CapitalSource is a real estate investment trust.

Fremont was once one of the largest U.S. providers of subprime mortgages before regulators ordered it to stop making the loans and asked it to divest the bank.

The firm had already warned in May that it may have to file for Chapter 11 relief. As it had stopped producing audited financial results, the company had to file for bankruptcy to be able to proceed with the sale of its unit's assets.

Fremont said its subsidiary was not part of the bankruptcy filing.

(Reporting by Muralikumar Anantharaman; editing by Gunna Dickson)