Millions of Argentines who crammed the streets of Buenos Aires to celebrate an unforgettable moment with Lionel Messi and his World Cup winning teammates instead found themselves at a giant party bereft of its hallmark bus parade.

Friends, families, even rival fans traveled from across the country to the capital to bask in the glory of a first world title in 36 years.

Yet most ended up missing the main show after the chaotic bus trip was aborted nearly five hours after it began, with police deciding it could not go on for security reasons.

Despite the disappointment, the festivities continued for many, with the day becoming an exhibition of Argentines' effervescent passion for football.

With almost everyone dressed in the team's distinctive blue and white jersey on a baking hot day, a unified presence masked the deep social fissures and economic inequality of a country grappling with years of financial turmoil.

It was an unprecedented party with an estimated five to six million people taking to the streets of Buenos Aires.

"I can't explain this (feeling) with words but with emotion," Paola Zattera, 43, who works in administration, told AFP.

She was six years old the last time there was a World Cup victory parade in Buenos Aires, when the late Diego Maradona was the people's champion.

She said she "didn't understand much" about what was going on back then but this time was determined to make the most of it.

"I don't care if I only see them from afar. I'm here and this is historic!"

- 'We can't organize anything' -

From early morning there was a constant swarm of people flowing down every road leading to the iconic Obelisk monument in central Buenos Aires, where the World Cup winners were due to end their 30-kilometer (18-mile) victory parade.

The fans had come from far and wide.

"We made the decision yesterday at five o'clock in the afternoon. We booked a hotel at the Obelisk and got on an airplane at four in the morning," 42-year-old night club owner Cristina Vazquez, from the southern tourist hub of Bariloche, told AFP.

"We're from Rosario, Messi's city," said merchant Luciano Peralta, 41, referring to the star's hometown some 300 kilometers northwest of the capital.

"There is hope at every World Cup but this team is very close to the Argentine people who identify a lot with them."

People from every walk of life mingled among the heaving crowds that even included families with small children and babies.

It was one party no one was prepared to miss, even after celebrating long into the night on Sunday after Argentina won the World Cup by beating France on penalties.

And yet, as so often before in Argentina, there was a sting in the tail.

Safety concerns were raised after some fans tried to jump into the bus from a bridge, and the remainder of the trip was canceled.

A hastily arranged helicopter tour that took Messi, Scaloni and midfielder Rodrigo De Paul over the main parade sites was little consolation for those who had hoped to see them in the flesh.

"I'm a little bit disappointed because once again we Argentines have shown that we cannot organize anything," lamented Jorge Ortalli, 52, who had come to Buenos Aires with his son from the nearby city of Campana.

- 'A memorable, eternal day' -

A constant din of drums and horns still filled the air hours after the aborted parade.

Earlier in the day, fans had clambered on top of bus shelters and up lampposts as the blue and white ripple of fans extended ever farther from the Obelisk.

Being present and mixing with fellow Argentines was what mattered to many.

"In 10 or 20 years we will remember that we were here, it's unique," said Agustin Deleriche.

"Whatever color, whatever social class ... winning a World Cup unites a country and those that experience it will never forget it."

He expected it to be a "memorable, eternal day."

But once again in economically unstable and politically polarized Argentina, there was a feeling among some of yet another missed opportunity.

"I would have liked it to end differently. We underestimated what could happen," said Roman Garcia, 38.

By the end of the day, minor clashes had broken out between fans -- some clearly inebriated -- and police who moved to evict a small group that had forced its way into the area around the Obelisk.