GREELEY, Colo. (AP) -- JBS Swift Beef Co. of Greeley, Colo., is voluntarily expanding its beef recall to include about 380,000 pounds of products because of possible E. coli contamination.

A recall earlier this week involved about 41,000 pounds of products.

The U.S. Department of Agriculture said Sunday that all the beef products in the expanded recall were produced April 21 and are in boxes bearing "EST. 969," a package date of "042109" and a time stamp ranging from "0618" to "1130."

The USDA says an investigation by its Food Safety and Inspection Service of 24 illnesses in multiple states prompted the company to re-examine its food safety system. The department says 18 of the illnesses appear to have the same cause, and the company is conducting the recall "out of an abundance of caution."

The USDA didn't immediately have an update Sunday of what states had reported illnesses or received beef products covered by the expanded recall. But the earlier recall covered products that were made April 21-22 and shipped to Arizona, California, Colorado, Florida, Illinois, Michigan, Minnesota, Nebraska, Oregon, South Carolina, Tennessee, Utah and Wisconsin.