Dr. Michelle Fiscus, a former Tennessee top vaccination official, told state investigators in July that she believed she was being threatened to keep quiet after receiving a dog muzzle in the mail, according to reports.

But according to a state investigation that concluded Monday, the muzzle was bought with an American Express card in her name off Amazon, NBC News reported.

“There is no evidence to indicate the dog muzzle was intended to threaten Dr. Fiscus,” according to a report from the Tennessee Department of Safety and Homeland Security.

Fiscus has denied sending herself the dog muzzle, tweeting Monday night that “the state’s investigation did NOT conclude I sent the muzzle.”

“In fact, it only concluded my credit card was charged with the incorrect billing address – my state work office – to an Amazon account I didn’t know existed,” she said in the tweet.

“That account was apparently accessed from the State of Washington, where I had never been, by a cell phone using a carrier I have never used,” she continued in another tweet. “I have asked the state for the full unredacted report and am awaiting a response.”

Fiscus was fired in July amid controversy over vaccine access for teenagers, NBC News reported.

Although Fiscus said her termination was political, state documents say she was fired over ineffective leadership and management and alleged failures to maintain good working relationships, the Nashville Post reported.

The state investigation was launched July 7 after a doctor with the state Health Department expressed concern that the muzzle was intended as a threat, according to the report from TDSHS.

Fiscus initially thought the muzzle had been sent to her as a joke by a coworker, but when the colleague denied sending it, Fiscus told investigators that she interpreted it as a veiled threat, NBC News reported.

“Dr. Fiscus said she felt it was a threat and that she should stop talking about vaccinating people,” the report from TDSHS said. “Due to her role in the vaccination program and her authoring a memo on Tennessee’s ‘Mature Minor’ Doctrine that she had been singled out for criticism by some people in the public, as well as several Tennessee Legislators.”