In the quarter ended March 31, International Bancshares earned $33.5 million, or 49 cents per share, compared with profit of $18.6 million, or 27 cents per share, in the first quarter last year.

International Bancshares said its prior-year results were hurt by an investment loss of $13.1 million.

The bank, which runs 260 branches in Texas and Oklahoma, said it maintained sound underwriting standards. The bank never issued "subprime" loans, or loans to people with bad credit. All of International Bancshares' loans are eligible to be sold to government-sponsored agencies.

As of March 31, the company had total assets of $11 billion, down from $11.1 billion at the end of the fourth quarter. Total loans remained flat at $5.5 billion, and deposits were unchanged at $7.2 billion.

Shares of the company added 24 cents to $25.23 in afternoon trading.