In the first call, a worker told dispatchers that an employee was sick in a restroom, vomiting and feeling fatigued. The caller raised the possibility of food poisoning and mentioned a homemade rice dish as a potential source.

In a later call, the employee reported that more workers had become ill, with at least four described as very sick. The calls document how quickly the response grew, but they do not establish what caused the illnesses.

The Tennessee Department of Health is investigating a possible foodborne illness connected to a meal at the facility. Walmart has said the fulfillment center is not open to customers and that products there and at nearby Walmart stores are not at risk.

The investigation’s findings could help determine whether the illness was linked to a shared meal or another cause. No confirmed source was identified in the information released about the calls.