Dozens of people are expected to show up to a demonstration in Waterloo, Ont. on Saturday, a week after three topless women were stopped by police.

Alysha Mohamed and her two sisters, Tameera and Nadia, were on an evening bike ride in Kitchener-Waterloo on Friday when they were pulled over by a police officer.

The women had been biking in the downtown area with their shirts off because of the heat, Brilla told CTV Kitchener.

Mohamed, a Juno-nominated singer who is better known by her stage name Alysha Brilla, said the sisters had spoken to several people while on their bike ride, including a female police officer, and no one had complained about their wardrobe choices.

But towards the end of their ride, at approximately 9 p.m., Brilla said they were stopped by a male officer who told them to put their shirts back on.

"We passed by a cop in an SUV and he immediately makes a U-turn after seeing us from the front," she told CTV Kitchener over the weekend.

"He says, 'Ladies, you're going to need to put shirts on.'"

As the sisters began to argue with the officer, Brilla pulled out her cellphone and recorded the interaction. She said the conversation changed when she began recording.

"What are you stopping us for?" she can be heard asking. The officer asked her whether she had lights on her bike.

"He would have seen our lights shining on him and our helmets and everything," she told CTV.

Brilla said they told him they had a legal right to be topless, and shouldn't have been stopped at all. Women have had the legal right to expose their breasts in Ontario since 1996. Guelph, Ont. student Gwen Jacobs was arrested for walking home from class while topless in 1991. Jacobs was charged with committing an indecent act, but fought the charge and won five years later.

Brilla said she and her sisters went to a police station to file a complaint with the Waterloo Regional Police Service. Though no one was arrested or charged, Brilla said they never should have been pulled over.

She said at the end of the conversation, her objective was just to ensure that the police officer was aware that women are allowed to be topless.

Waterloo Regional Police Staff Sgt. Mike Haffner told that there are conflicting reports about what happened that night, but that the department is looking into the officer's conduct.

"We are continuing to conduct an internal review on the incident from Friday evening," Haffner said.

The sisters said they may also file a formal complaint with the Office of the Independent Police Review Director, which oversees all public complaints against police services in Ontario.

Haffner said he is not aware of any complaint made with the OIPRD, but that he will only be notified if the office decides to investigate further.

In addition to the possible complaint, the sisters are planning a pro-topless rally at Waterloo Town Square on Saturday.

"Women are still not truly free to be topless in public, without facing harassment from passersby and in some cases, uninformed police officers," a message on the event Facebook page said.

"On Saturday, August 1st, we invite all people of all genders to march with us revealing as much or as little of their torso as they feel comfortable (please wear sunscreen though) in solidarity to support women's right to be topless in public, and also to show support for desexualizing women's breasts."

The post invites people of "all body shapes and types," and any protesters of the event will be asked to leave.

The group will meet outside the Waterloo Public Library at 11 a.m. to make posters. There will be an opening speech at Waterloo Town Square at noon, followed by a march from the square.

With a report from CTV Kitchener's Allison Tanner