Thousands of people gathered in downtown Ottawa Sunday for what was billed as the biggest Pride parade in Ottawa's history, with two special guests making it a milestone year.

The streets were filled with rainbow flags and placards, carrying messages of diversity and love.

Capital Pride made history by having a sitting prime minister march in this year's parade, as Justin Trudeau walked down Bank Street with two of his children, flanked by other Liberal politicians.

Gen. Jonathan Vance also became the first chief of defence staff to march in a Pride parade.

Black Lives Matter protest briefly stops parade

Shortly after 2 p.m., however, protesters with the Black Lives Matter group temporarily halted the parade at Bank Street and Gladstone Avenue.

Protest at Bank and Gladstone just ended <a href="https://t.co/9lJuKfWcLJ">pic.twitter.com/9lJuKfWcLJ</a> —@juliasisler

The protesters provided a list of 20 demands, some which echoed similar demands by Black Lives Matter protesters in Toronto, including not allowing officers to march in uniform, have weapons or Pride-themed vehicles in the parade.

They also requested a bag check area for participants to leave their belongings, accessible childcare spaces and free transportation after Pride events.

One item the group wants reinstated is the terms of reference for the Ottawa Police Service's GLBT liaison committee, along with a commitment to implement suggestions from the committee and incorporate LGBT members in police governing bodies.

'Our voices and our lives have no weight here'

Activist Leila Moumouni-Tchouassi says some of the people who started Pride events are being erased from continuing conversations. (Raphäel Tremblay/CBC)

For activist Leila Moumouni-Tchouassi, her goal in participating in the protest was to remind people that black transgender women have been increasingly erased from Pride-related conversations and events, she told Radio-Canada in French.

"Our voices and our lives have no weight here," she said.

Black Lives Matter activists had met with Capital Pride executive earlier in the summer, but Moumouni-Tchouassi said not much transpired from the meetings.

Pride's executive had asked civilian police officers not to wear their uniforms, but that didn't go far enough for her.

She added that while she didn't see civilian police marching in the parade, having police provide security is still a problem.

"Sadly, Ottawa remains a violent city for people of colour and activists," she said.

A group of activists plan to meet with Capital Pride's executive later on to discuss their newest demands.

Black Lives Matter protesters outlined a list of 20 demands they want implemented ahead of next year's Pride celebrations. (Florence Ngué-No/Radio-Canada)

Senior military leadership take part

Vance, Canada's top general, led a contingent that included many of the military's most senior leadership through downtown Ottawa Sunday.

In a Canadian Press interview before Sunday's march, Vance said he wanted to show members of the LGBT community already serving in the uniform that he and the rest of the top brass support them — and also spur those community members to think about a career in the armed forces.

"We know for sure that a more diverse workforce, drawn from the incredible talent from across Canadian society — and particularly Canadian youth — is what will make us the strongest we can be in the future. Failure to do that, we will not be capitalizing on the excellence within the Canadian population," he told CBC News at the parade on Sunday.

Le général Jonathan Vance, premier chef d'état-major à participer à un défilé de la Fierté au pays <a href="https://twitter.com/hashtag/iciottgat?src=hash">#iciottgat</a> <a href="https://t.co/Bea4pjzZ0W">pic.twitter.com/Bea4pjzZ0W</a> —@fngueno

Prime Minister Justin Trudeau also marched in the Ottawa parade with two of his children and lauded Gen. Vance's participation.

"It's just an emphasis that we are a country open to diversity and we know that it's one of our strengths, whether it be in the military or everywhere else."

Prime Minister <a href="https://twitter.com/JustinTrudeau">@JustinTrudeau</a> became the first sitting PM to march in Capital Pride. Defence chief Gen. Jonathan Vance also marched <a href="https://twitter.com/hashtag/ottnews?src=hash">#ottnews</a> <a href="https://t.co/8wUBZdDiDN">pic.twitter.com/8wUBZdDiDN</a> —@KimberleyMolina

Police chief marches in orange golf shirt

Ottawa Police Service Chief Charles Bordeleau also marched in the parade, albeit in an orange Ottawa police golf shirt rather than his full uniform.

Bordeleau had initially vowed to wear his official police regalia but backtracked after weeks of discussions following Capital Pride's request that officers leave behind their uniforms and cruisers.

Check out some more photos from this year's Pride parade.

David Greene visited from Cleveland, Ohio, and says Pride means a lot to the generation who survived the AIDS epidemic. (Trevor Pritchard/CBC)

Capital Pride is the testing ground for new social media safety awareness campaign. (Trevor Pritchard/CBC)

A man dons a pair of Pride wings as he marches in the Ottawa parade. (Raphäel Tremblay/CBC)

Natalie Lloyd is part of a local LGBT curling group and brought her rainbow broom with her to the parade. (Trevor Pritchard/CBC)

Gen. Jonathan Vance, Canada's chief of defence, shakes the hand of a potential future member of the Canadian Armed Forces. (Trevor Pritchard/CBC)

Members of Ottawa's Indigenous community march in the Pride parade on Aug. 27, 2017. (Waubgeshig Rice/CBC )

Even OC Transpo went rainbow, flying the Pride flag on one of its buses taking part in the Pride parade. (Trevor Pritchard/CBC)

Even a rainbow car took part in this year's Pride parade. (Raphäel Tremblay/CBC)