The U.S. Food and Drug Administration said it is investigating the latest outbreak of cyclosporiasis in the United States. 

The Centers for Disease Control and Prevention (CDC) has been notified of about 358 confirmed cases of the infection until Thursday, the FDA said in a statement on its website. 

The agency said it has not identified a "conclusive vehicle" for the latest outbreak, but preliminary investigations found that cilantro from the state of Puebla, Mexico was supplied to restaurants at which some of those who have become ill ate.

Fresh cilantro from Puebla has been linked by health officials to the 2013 and 2014 annual cyclosporiasis outbreaks as well.

U.S. officials earlier this week implemented a partial ban on imports of the herb from the area, after human feces and toilet paper were found in growing fields and around facilities. 

Wal-Mart Stores Inc and Kroger Co are pulling some cilantro from stores, Bloomberg reported on Wednesday

The 2015 outbreak has been confirmed in 26 states, with clusters of illness identified in Texas, Wisconsin and Georgia, the agency said.

The parasite, cyclospora cayetanensis, infects the small intestine, typically causing watery diarrhea, and frequent, sometimes explosive, bowel movements. It is spread by ingesting something - such as food or water - contaminated with feces.

If untreated, those infected could experience no symptoms at all, or have them come and go, or have them last from a few days to a month or longer.