Alberta's police watchdog is investigating after a Lethbridge officer drove over an injured deer multiple times with his vehicle to try and kill the animal.

Lethbridge Police Service said in a release Tuesday that it was contacted Monday by a local media agency that had obtained a video of an on-duty officer using a police truck to drive over the animal along the 1600 block of Scenic Drive South.

Chief Rob Davis reviewed the video, then notified the director of law enforcement and triggered an Alberta Serious Incident Response Team (ASIRT) investigation.

"After watching the video, I understand the concerns people have and I can assure the community we take this incident very seriously," said Davis in the release.

The officer will continue to work at his usual position while the investigation takes place.

ASIRT will be reviewing the officer's actions, and the police service's policy for responding to injured animal calls.

'Disappointing': SPCA

Dan Kobe, communications manager for the Alberta SPCA, said he's seen the video and was disappointed by the officer's actions.

"As an organization, the Alberta SPCA would expect that any animal, if it's injured and needs to be put down, it would be euthanized in a humane way," he said.

"Certainly, looking at that video, I think everyone can agree that was not a humane way to put down that deer and it's disappointing to see that's the method that was chosen to put the deer down."

The SPCA is only responsible for livestock and pets, so Kobe said it would not be investigating the incident. CBC has reached out to Alberta Fish and Wildlife for comment to see if it will also be investigating the incident, along with ASIRT.

Lethbridge police said they will not be providing any further details while ASIRT's investigation takes place.

An online petition calling for the officer in question to be fired had gathered thousands of signatures by Tuesday evening.