BBCN Bancorp Inc. announced late Monday that Alvin Kang, the bank holding company’s chief executive, will resign effective Jan. 31. Kang is also resigning from his post as a director of the company.

BBCN, which operates the $5 billion-asset BBCN Bank, the largest Korean-American bank in the country, said it will hire a search firm to find a new chief executive and has appointed an executive council to lead the bank in Kang’s absence.

Kang became chief executive of Koreatown’s Nara Bancorp in 2010 and led it through its merger with Center Financial Corp. the following year, creating BBCN.

BBCN did not say why Kang was resigning. In a statement released after markets closed Monday, Kang thanked BBCN employees and said the bank has a “strong foundation to capitalize on exciting opportunities ahead.”

Analysts suggested BBCN might be interested in acquiring Hanmi Financial Corp., also of Koreatown, which announced last week it had hired a financial adviser to consult on a possible sale or merger.

Shares of BBCN closed at $11.89, down about 4 percent from Monday’s close of $12.36.