An online petition calling for the firing of a Lethbridge, Alta., police officer who was filmed killing a deer with his vehicle has garnered more than 46,000 signatures from around the globe.

"I'm actually very surprised that it's gone worldwide," Tara Daubert, who started the petition, told CBC Calgary News at 6.

"From signatures I've actually seen … New Zealand, India this morning, Greece, and of course, all over Canada and the United States, I'm surprised it's made it this far but I'm also happy it's garnered such a response to this little deer."

Daubert started the petition in response to a video, originally published by Global News, which shows on-duty officer using a police truck to drive over a deer multiple times in south Lethbridge, trying to kill it for nearly 15 minutes.

The animal eventually died.

Daubert said she hopes the officer is charged with animal cruelty.

"Then I'm hoping that he does get removed from his position," she said. "I believe that as a police officer you're here to protect and serve and you're a role model to the community, and I believe that what he did was not being a role model at all."

Tara Daubert created a petition calling for the firing of a Lethbridge police officer who was filmed driving over an injured deer multiple times to kill the animal. (CBC)

The Alberta Serious Incident Response Team (ASIRT), which normally reviews police officers' use of force on other humans, is taking the exceptional step of investigating the case. It's the watchdog's first file involving an animal. Alberta SPCA and Alberta Fish and Wildlife are assisting with the investigation.

In another rare move, ASIRT issued a lengthy statement Wednesday afternoon about the open investigation.

"It is recognized that this is an extremely sensitive and serious matter where there has been considerable public interest," the agency said.

"ASIRT will examine a police officer's powers relating to dealing with events such as this and will consider the relevant provisions within the Criminal Code, the Animal Protection Act and Wildlife Act."

The officer will remain on duty during the investigation.

Anyone who encounters an injured animal should call Alberta Fish and Wildlife at 403-310-0000, or here is a list of the department's regional offices.

A protest is planned for outside police headquarters in Lethbridge on Sunday.