A report released Wednesday by the Southern Nevada Health District said the salmonella contamination likely occurred at the Firefly Tapas Kitchen & Bar, not where the sausage was produced, the Las Vegas Sun reported.
"[There is] a small possibility that raw chorizo was contaminated prior to arriving at Firefly," the report stated. "It is likely that the outbreak was due to local cross-contamination in the restaurant's kitchen and not from a contaminated commercial food."
At least 294 people from 27 states and two other countries became ill after eating at the popular restaurant last month and health officials said the final tally could be higher, the newspaper said.
Firefly owner John Simmons said the restaurant, which was closed after the outbreak, has hired a food-safety consultant "double and triple check our methods and we'll operate in the mode of continuous improvement, constantly upgrading our practices with new technology, new methods and additional training."
"From Day 1, our concern has always been doing everything we could for those affected and doing everything we could to use this time to make Firefly the safest place to eat in southern Nevada," he said in a statement. "While we are anxious to have the final report and a better idea of what may have happened, for me, it was never about the source -- it was about making sure I did everything in my power to prevent this from happening again."