MONTREAL -- The Montreal SPCA is mounting a legal challenge against the city over its newly adopted pit bull ban, the animal-welfare organization announced Wednesday.

Animal advocacy director Alanna Devine said the SPCA filed court documents asking a judge to stop some portions of the new law from coming into effect.

"What we're asking as a first step is a judge from Quebec Superior Court suspend the application of the sections of the bylaw that deal with 'pit bull-type dogs' in order to eventually have these sections be eventually declared illegal, null and without effect," she told The Canadian Press.

The SPCA alleges the sections that specifically target pit bulls are discriminatory and contrary to Quebec's animal-welfare laws that define animals as "sentient beings."

Devine said they're also unreasonable.

"They treat all pit bull-type dogs as dangerous despite the fact there exists no credible evidence that dogs belonging to this arbitrary looks-based category are inherently dangerous," she said.

Montreal city council voted 37-23 in favour of the new bylaw Tuesday following a heated debate on the issue.

The legislation includes a ban on new pit bull-type dogs as of next week.

It also places restrictions on those currently in the city, including the requirement that they be sterilized and wear muzzles in public.

The law was drafted following several attacks, including one last June that resulted in the death of a 55-year-old woman in her backyard.

A spokesperson for a coalition of legal and other experts formed to oppose the ban says her group is also ready to challenge the law in court.

Sabrina Sabbah, a co-founder of the group, says the coalition will offer legal and other forms of support to citizens who are affected.

"If people have issues, whether it's with the police, canine inspectors, or with the city, they have a source of information and they have people willing to take this to court for them," she said.

In a statement released late Wednesday, the city said the new legislation falls within established municipal rights.

"The power to adopt regulations on animal-control matters, notably to improve the safety of citizens, is a recognized municipal purpose," it read.

When questioned on the issue Tuesday, Montreal Mayor Denis Coderre said the legality of such bans have been upheld in several other jurisdictions, notably in Ontario following the announcement of a provincewide ban in 2005.

Several other cities in Quebec and across Canada already have bans in place. The Quebec government is also considering provincial legislation regarding the dogs.