What are the mystery canines that are terrorizing Thornhill?

Two aggressive mystery canines are still on the loose in Thornhill, Ont., where they have terrorized residents and police officers alike.

"There's been no further sightings," York Regional Police Sergeant Clint Whitney said. "The public's been advised. Everyone's been notified and now we're waiting for information."

Despite several sightings earlier this week, there is no consensus on what species the violent animals are.

The canines bit two women on Monday, causing minor injuries. They also chased several people into their homes, including a man who fended them off with a rake.

York Regional Police officers searching for the animals used pepper spray and even a bullet to keep them at bay.

After being lunged at in a backyard, an officer repelled the pair with pepper spray on Monday. And later in the day, an officer shot one of the animals in the shoulder before it ran into a wooded area.

"At that point, without any tranquillizers available or any other viable alternatives to safely put them in, they were deemed to be a threat to public safety and that's why the shot was fired by that officer," Sgt. Whitney said.

There is broad disagreement among witnesses – including police officers – about precisely what kind of canines the animals are.

"There's some people who will swear that it's a German shepherd and others who will adamantly say it was a coyote and those who believe it's a coy-dog or a coy-wolf, a hybrid of some kind," Sgt. Whitney said.

"You're having all kinds of people weigh in with different opinions, but until we actually have the animals, we won't know for sure. … The safest thing to say is that they're undomesticated canines of some sort. Large and vicious."

Animal scientists say wolves and coyotes began mating in Ontario in the early 20th century, and some believe that a hybrid species has ventured into urban areas.

Residents in Thornhill and staff at a golf course have told police that a pair of coyotes has lived in the area for the past two years. But is unclear whether the aggressive canines are the same animals.