Health regulators said cantaloupe from Chamberlain Farms in Indiana may be one source of a multi-state outbreak of salmonella that has killed two people and sickened some 178 in the past month.

The farm in Owensville in southwest Indiana decided to recall all its melons, which were first shipped within the state and to Illinois, Kentucky, Missouri, Ohio, Tennessee and Wisconsin. The melons may have later been shipped to other states, the U.S. Food and Drug Administration said late on Wednesday.

The FDA and others are still trying to figure out if there are other sources of the salmonella outbreak, which has spread to 21 states so far and sent 64 people to the hospital. Last week, they said they are also looking at watermelons as a possible source of a smaller outbreak.

Regulators already knew the salmonella outbreak that began in early July likely started in Indiana, but had not previously pinpointed any farms that may have been responsible.

The illness from the food borne organism usually causes a week-long bout of diarrhea, fever and abdominal pain. But it can be fatal for the elderly, young children and people with weakened immune systems. Thousands of Americans contract salmonella illness each year, often from uncooked chicken.

The current salmonella outbreak comes after cantaloupe tainted with Listeria and traced to a Colorado farm killed 30 people across 11 states last year, in the deadliest U.S. food borne illness in over a decade.