BEIJING -- China's central bank said on Friday that bad loan balance had posted the first increase in eight years, warning rising financial risks in a range of sectors.

The bad loan balance stood at 1.07 trillion yuan ($173.7 billion) at the end of 2012, an increase of 23.4 billion yuan from the year beginning, the People's Bank of China said in its 2013 financial stability report.

The non-performing loans ration was 1.56 percent, down 0.22 percentage points from the year beginning.

The balance of defaulted loans of commercial banks was 528.1 billion yuan, surging 46 percent from the year beginning, indicating possibilities of more bad loans in the future.

Defaulting risks are mainly found in the Yangtze River Delta where market economy and small enterprises proper. Overbloated industries, including solar panel manufacturing, iron and steel making and cement, are hit by the perils.

The report also singled out the potential dangers of the wealth management products of which part of the money were put to industries that restricted to bank lending.