The Bank of China (BOC), one of the country's four largest state-owned commercial banks, said its after-tax profits rose by 40 percent to 45.5 billion yuan (6.1 billion U.S. dollars) in the first nine months of the year based on the international accounting rules.

The bank contributed the leap in profits to the rapid increase in net interest income and earnings from intermediary services.

Its net income from interest rose 26.7 percent year on year to 110.6 billion yuan (14.8 billion dollars).

The commission charges from distribution and entrusting of mutual funds and corporate intermediary businesses expanded by 88.9 percent to 18.9 billion yuan (2.53 billion dollars) in the Jan.-Sept. period.

The bank said its income from other than interest rose 32.7 percent to 26.7 billion yuan (3.57 billion dollars) to account for nearly 20 percent of its total turnover.

It said the non-performing loan ratio continued to drop, without revealing the exact figure.

The lender said its business turnover per capita reached 319,400 yuan (42,757.7 dollars) in the first three quarters, up 34.9 percent from the same period last year, leading all the other domestic commercial banks.

By Sept. 30, the bank's total assets hit above six trillion yuan (803.2 billion dollars), said the bank.

The rival Industrial and Commercial Bank of China (ICBC), the country's largest lender, had reported a 66 percent year-on-year increase in its net profit in the first nine months of this year.

The BOC also revealed it held about 7.95 billion dollars of debt obligations related to the U.S. sub-prime mortgage by the end of Sept., already down by 1.7 billion from the end of June.

It had booked another 322 million dollars of devalue provision for the risky debt obligations in the past three months, and the balance of the provision stood at 321 million dollars by the end of September.

Share prices of the Bank of China on the Shanghai bourse fell to 7.14 yuan on Wednesday's closing.