Lawyers representing a disgraced egg industry titan, his son and one of their company's officers say their clients are potential targets of a criminal investigation into the 2010 salmonella outbreak that sickened thousands of Americans.

In recent documents filed in a civil case in California, lawyers for Jack and Peter DeCoster and Quality Egg Chief Financial Officer Patsy Larson say a federal grand jury has been meeting to determine whether fraud or other crimes were committed in the production and testing of eggs in Iowa.

Larson's attorney says his client has been subpoenaed to testify next week.

Des Moines attorney Jan Kramer, who is representing Jack DeCoster, says former Quality Egg officers have testified.

A spokesman for federal prosecutors says he cannot confirm the investigation.