Introduction - In January 2010, two hepatitis A clusters were identified through mandatory reporting (MR) in the Lot and Hautes-Pyrénées departments. The cases, which were infected by a single viral strain, had in common that they had visited sandwich shops belonging to the same chain. Due to the identification of additional cases by the National Reference Center (NRC) for Hepatitis A Virus (HAV) in other departments, a national epidemiological, virological, and veterinary investigation was conducted to identify the source and propose control measures. Methods - Cases were identified through mandatory reporting and the NRC. A case-control study was conducted. Results - A total of 59 cases were identified in 19 departments. Consumption of sandwiches or salads at a sandwich shop and consumption of semi-dried tomatoes were significantly more frequent among cases than controls, 83% vs. 17% (adjusted OR 29.1 [9.7–87.0]) and 67% vs. 27% (adjusted OR 8.5 [4.4–30.2]). The sandwich shops were supplied with semi-dried tomatoes imported from Turkey by a common supplier located in France. Conclusion - The results of the investigation suggest that this national hepatitis A outbreak was associated with the consumption of semi-dried tomatoes imported from Turkey. The importation of food products from countries with high HAV endemicity can lead to outbreaks in countries with a growing proportion of their population that is unimmunized. (R.A.)