Mizuho Bank tried to sell fixed low-interest housing loans without telling customers that there was a possibility the interest rate could actually rise before they got them, sources said Thursday.

The Fair Trade Commission plans to warn to the bank, the core unit of Mizuho Financial Group Inc., that it is potentially in violation of the law, the sources said.

In March, Mizuho Bank started marketing a housing loan advertised as having a fixed interest rate of 2.25 percent for 10 years. Customers had to sign up by March 31 and would receive the loans by June 30.

However, the bank failed to inform customers that there was a chance the interest rate could climb before the loans were handed out, they said.