Investigators found no evidence that employees at an Aurora Taco Bell laced an irate customer’s food with rat poison last weekend, according to a news release from the Arapahoe County Sheriff’s Office.

The office is asking the customer to contact them after multiple attempts to reach him, including via visits to his home Thursday, went unanswered.

The incident began at about 1 p.m. Sunday when deputies were called to the restaurant at 16700 E. Smoky Hill Road in Aurora. The customer had been arguing with Taco Bell employees after they told him their soda machine was broken. The restaurant workers eventually gave him a burrito instead of a drink.

That evening, the man was admitted to a local hospital, telling health care workers he ate rat poison. He told deputies that he had eaten the tacos at about 7 p.m. after helping a neighbor with yard work and watching television. He immediately felt a burning sensation in his mouth and vomited. He called 911 and was taken to the hospital, along with the taco.

Deputies called to the hospital found a greenish-gray substance in the taco. Tests confirmed it was rat poison, according to the news release. The Taco Bell was immediately closed. No one answered the phone number listed for the restaurant at about 11:15 a.m. Friday to indicate if it was now open.

Investigators spent the next several days watching video from inside the Taco Bell and found no evidence that employees laced the food with rat poison. The sheriff’s office cannot account for how the poison ended up in the food. Officials with the sheriff’s office have not been able to contact the customer and ask that he contacts the office.

The office said Taco Bell had been “very helpful during the investigation,” according to the news release.

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