BEIJING -- The National Audit Office (NAO) on Thursday said it has found that some State-owned financial institutions have violated lending regulations.

NAO said 27 branches of State-owned financial institutions provided loans worth a combined total of 28.44 billion yuan ($4.6 billion) for projects without proper procedures or necessary guarantee.

Nine branches charged extra fees totaling 421 million yuan for small business loans and export credit services, auditor general of NAO, Liu Jiayi, said in an auditing report presented to the country's top legislature.

Meanwhile, 18.39 billion yuan was embezzled by clients and 2.2 billion yuan was transferred to private financial markets for usurious loans, NAO said.

NAO said 22.03 billion yuan in illegal or embezzled loans has been retrieved and authorities have prosecuted 693 people in relation.