A once-in-a-lifetime celebration for Toronto Raptors fans on Monday was not without organizational problems, as millions of people waited to greet the NBA champions for the first time since their historic win.

Despite what city officials say was "intense" planning, the Raptors victory parade saw hours of delays amid euphoric chaos. Many people were left stranded without water or sufficient bathroom facilities in the midday heat. Others climbed traffic poles and buildings, or watched atop trucks to get a better view.

With no barricades to keep people off the main parade route, frenzied fans clogged the streets to join in the party just days after the Raptors beat the Golden State Warriors in Game 6 of the NBA Finals. This caused huge lags as the motorcade carrying the team and the trophy inched along, trying not to hit people jammed together like sardines along the sides of the five double-decker buses. The parade took more than four hours to wind its way through downtown Toronto, and the city came to a virtual standstill.

Brad Ross, the city's chief communications officer, insisted there were barricades set up along the five-kilometre route to keep the crowds back, but "in their exuberance," a wave of revellers dressed in red, white and black jumped over them.

"They were quickly ignored and people just took to the streets in an attempt to celebrate and be close to the team," he said Tuesday in an interview with CBC Radio's Metro Morning.

"Yes, it slowed things down significantly, but overall people were having a very good time, and that was really the point of the entire day."

The parade shut down parts of Toronto's downtown area for cheers, chants and champagne showers. 7:48

Maple Leaf Sports and Entertainment (MLSE), the corporation that owns the Raptors and hosted the official championship parade and rally, had expected two million people to attend the momentous event.

The organization said in an email that a water station was available at Nathan Phillips Square, but not along the main parade route where staff were handing out water to spectators instead.

MLSE said in a statement on Tuesday it will "implement appropriate measures for future events of this scale."

When compared to other NBA championship parades in other cities in recent years, Toronto's celebration unfolded in similar fashion. Here's a look at what happened during the last three victory rallies:

Oakland, Calif., in 2018 and 2017: Gunshots were fired and people were wounded, children were separated from their parents, and people took to the streets and blocked the parade route.

Gunshots were fired and people were wounded, children were separated from their parents, and people took to the streets and blocked the parade route. Cleveland in 2016: Fans hopped barriers and flooded the streets to get a closer look at players in the parade, a shooting wounded a woman, children got lost in the crowd, and people suffered from dehydration.

Ross described the parade as a "celebration event," as opposed to a "security-type event where the objective is to keep people out."

He noted there was a big difference from how the City of Toronto and police treated the turbulent G20 Summit in 2010, which saw violent street protests and mass arrests as global leaders gathered in a fortified block of downtown.

"The objective here was to allow people to have fun and to celebrate, and police made those decisions with public safety in mind, of course," he said.

Ramped up security measures were still in place, Ross said, such as dump trucks that were positioned as blockades along major thoroughfares. Stretches of several roadways were also closed off to traffic.

First responders attended to an injured person after gunshots were fired during the parade. (Tijana Martin/Canadian Press)

Still, the victory celebration was later marred by violence.

Hundreds of people were sent fleeing after gunshots were heard around 3:45 p.m. ET at Bay and Albert streets — near the southeast corner of city hall and Nathan Phillips Square.

Although the rally continued with Prime Minister Justin Trudeau and Ontario Premier Doug Ford on stage, the shooting left four people wounded, and three people were taken into custody.

Canada's largest municipal police force deals with mass situations on a regular basis, Chief Mark Saunders said, pointing out that the right resources were in place for officers to quickly respond.

"Our role is not to predict what is going to happen. Our role is to be intelligence-led and also understanding of the environment and what we need to have the capability of transitioning into."

Mayor John Tory told city council on Tuesday that anger still prevails over someone bringing firearms to the mega-celebration. However, he lauded the "extraordinary" team effort of MLSE, city officials, first responders and the transit authority to pull off the parade with only a few days notice.

"This was a massive event, the likes of which our city has never seen before," Tory said.

Maple Leaf Sports & Entertainment – with the help of City staff and Toronto Police – had three days to plan this parade. I want to thank everyone involved in this effort – especially our City staff in countless departments including transportation, TTC, & solid waste management. —@JohnTory

Fans began filling the downtown area on the weekend, after last Thursday's historic victory in Oakland, Calif.

According to the City of Toronto's estimates, more than one million revellers swelled the parade route in order to catch a glimpse of the Raptors. Another 100,000 fans packed into Nathan Phillips Square — the final destination of the parade route and the scene of a late-afternoon rally that started more than three hours late.

This was the scene as fans lined up along the exit ramps during the parade. (Albert Leung/CBC)

When asked if officials underestimated the volume of people who would come out to celebrate the Raptors, Ross responded, "I don't think so. We knew that there would be a large contingent of fans who would come out to celebrate and to see their team, and then take part in this parade and the rally in the square."

City officials looked to previous NBA victory parades in other U.S. cities — like Cleveland, which saw some two million people take to the streets — when planning Monday's parade, he said.

"What was probably underestimated was just, you know, the barricades and the like would just be simply ignored and they would just take to the streets and surround the parade contingent."

City manager Chris Murray added that staff will work with police and the TTC to review details of Monday's parade to see how Toronto can improve in case other sports teams have similar success in the future.