Or rabid. You're right about the feral dog possibility, more likely to attack a human than a wolf and certainly a coyote. But if the RCMP shot one, they must know what it was, though the media might mess it up. A tragic incident, regardless of the culprit.
Probably not “rabid,” if you mean infected with rabies. One time I was able to coax a friendly beagle out of the feral pack. He didn’t belong. Took him to the local animal shelter. The pack leader was a huge mutt, probably weighing 180 lbs. plus. Saw him take down a buck in my driveway. I got stupid - not armed at the time - and charged him and he ran off. I was lucky because he had big teeth and all had was trimmed fingernails, a nice haircut and tennis shoes.