A Windsor, Ont., chihuahua that can easily fit inside a purse has been designated a dangerous dog after a letter carrier claims it bit her on an ankle.

The woman didn't want to make a big fuss about it, but her manager decided to file a police report on the dog attack based on Canada Post policies.

The designation means the owner is required to muzzle Molly, which weighs three pounds, and display a dangerous dog warning sign on the property because officials say "it's a danger to society."

"We don’t even know if we can find a muzzle because her mouth is so tiny," said owner Mitzie Scott.

Mitzie and her husband Jason own the dog and said the designation is a joke.

"We have to warn people upon coming onto our premise that we have a vicious dog on site," she said.

The city is also forcing the couple to purchase a $1-million insurance policy on the chihuahua.

"It just seems so severe to me. We love the dog and we can’t get rid of the dog, but also that’s a very expensive monthly expense," said Mitzie.

Mitzie said her husband was doing yard work when it happened.

"I didn’t realize when I let the dog out that he had the side gate open and she kind of snuck out the front," said Mitzie. "I didn’t see anything, I just heard her bark."

Soon after the alleged bite, city and health officials arrived at the home and quarantined the dog, she said. The couple wanted to appeal the decision because they didn't see the bite mark, a picture or even a medical report.

Mitzie said the dog has never bit anyone before.

"I didn’t know what my dog did, maybe my dog jumped up and scratched her," said Mitzie "I didn’t see it, I just took her word for it."

Coun. Ron Jones is on the city's licensing commission and said this is not as silly as it may sound.

"Nowhere in the bylaw does it indicate that a dog has to be 50 pounds to be designated as a dangerous dog," said Jones

The decision is not sitting well with Windsor Mayor Eddie Francis. He's concerned about the attention this story is starting to get.

"Media is going to have fun with this one, and we'll probably get national attention on this one as well." said Francis. "Unfortunately, the owner of the dog, in my opinion, based on the information that has been shared with me, demonstrated mitigating factors that would have given the licensing commission opportunity to consider other options."

The biting incident happened in August while the postal worker was on her Matthew Brady Boulevard route in east Windsor.

The city's licensing commission rejected an appeal by Molly's owner, Jason, to reverse its decision.

"I don’t want to sound like I’m not taking responsibility because it’s my fault, she slipped out," Mitzie said. "She’s three pounds, sometimes accidents happen. I just thought the consequences were just so extreme."

The couple thinks a warning for the first offence would have been an appropriate punishment.