Security First Bank of Rapid City announced its merger with Nebraska's First National Beatrice Bank on Friday.

The resulting bank, which will be called Security First, has assets of $670 million.

In addition to Rapid City and Martin, Security First Banks are located in 13 Nebraska towns.

First National Beatrice Bank operated Nebraska branch locations in Beatrice, Blue Springs, Clatonia, Cortland and Lincoln.

In addition to the banking operations, both banks operate insurance agencies, which will also combine and do business as Security First Insurance.