The sporting program at the Paris Olympics endured a chaotic start on Wednesday as men's football kicked off while a huge police operation was put in place for Israel's first appearance at the Games.

Two days before the opening ceremony, Morocco beat Argentina 2-1 in Saint-Etienne, but only after a late equaliser for the South American side was disallowed and the final minutes were played out in an empty stadium following crowd trouble.

Argentina thought they had escaped with a 2-2 draw when Cristian Medina scored in the 16th minute of added time.

But as their players celebrated, projectiles including bottles and plastic cups rained down from the stands and several spectators entered the pitch, with the referee promptly blowing the whistle.

The teams left the playing area, but the referee had not blown for full-time and the outcome of the match was unclear until the sides finally reappeared two hours later to play out three more minutes in a stadium that was by now emptied of spectators.

Medina's goal was eventually disallowed for offside following a review and Morocco celebrated a 2-1 win.

"It is a disgrace that this should happen and poison the tournament," said Argentina coach Javier Mascherano.

Israel's footballers later Wednesday took on Mali under the watchful eye of 1,000 police officers, with authorities erecting an "anti-terrorist perimeter" and braced for possible disruption around the stadium.

Israel's participation in Paris has been a key talking point in the run-up, with calls from the Palestine Olympic Committee and some left-wing French MPs for the country to be excluded over the Gaza conflict.

Some Palestinian and Israeli flags were flown with angry words exchanged amongst some fans at the Parc des Princes in Paris.

However, French interior minister Gerald Darmanin said "there has been no security problems to our knowledge".

A packed Stade de France cheered on Antoine Dupont -- arguably the world's best rugby player and a pin-up of the Paris Games -- as he helped his team into the quarter-finals.

A 12-12 draw with the United States was followed by a nervy 19-12 win over Uruguay.

In the same pool, double champions Fiji also made the knockout round with back-to-back wins over Uruguay and the United States.

IOC warns Salt Lake

As the clock ticks down towards Friday's opening ceremony along the Seine, Olympic chiefs awarded the 2030 Winter Games to the French Alps and the 2034 event to Salt Lake City.

But in a dramatic twist they warned the US city could be stripped of the Games if American authorities kept up their feud with the World Anti-Doping Agency (WADA).

John Coates, the chairman of the IOC's legal commission, said the host city contract confirming Salt Lake's right to stage the Olympics had been altered to allow the IOC to strip it of the Games if US authorities did not respect the "supreme authority" of WADA.

The US anti-doping agency (USADA) has been a vocal critic of WADA for much of the past decade and tensions escalated this year after reports in April revealed that 23 Chinese swimmers had tested positive for a banned substance ahead of the Tokyo Olympics, but were subsequently cleared to compete at the Games.

USADA chief Travis Tygart accused Olympic bosses of "stooping to threats".

"Today's demonstration further showed that as it stands today, WADA is just a sport lapdog, and clean athletes have little chance," said Tygart.

Security lockdown

The Olympics lost a top star when tennis world number one Jannik Sinner withdrew with tonsillitis, with the Italian admitting he was "sad and disappointed".

Preparations for Friday's historic opening ceremony were in full swing with an unprecedented security operation for the athletes' parade along the River Seine.

Around 6,000-7,000 athletes are set to sail down a six-kilometer (four-mile) stretch of the river towards the Eiffel Tower, on 85 barges and boats.

Up to 500,000 people are set to watch in person from specially built stands, on the river banks and from the overlooking balconies and apartments.

The area around the river has been locked down before the ceremony, with snipers positioned along the route and frogmen deployed to prevent a waterborne attack.

The entertainment line-up for the ceremony, the first time a Summer Olympics has opened outside the main stadium, is yet to be fully announced.

But videos posted online showing US pop star Lady Gaga in Paris sparked rumors she will be among the performers.

American rapper Snoop Dogg will carry the Olympic flame this Friday as it makes its final rounds before the ceremony.

Scandals

In the first scandal of the Games, a video emerged showing the mistreatment of a horse by one of Britain's most decorated Olympians, dressage specialist Charlotte Dujardin, who has been suspended.

The film showed the three-time Olympic champion walking alongside a horse and repeatedly whipping the animal while apparently training a young rider.

Dujardin, 39, has won six Olympic medals and was aiming to become Britain's most successful female Olympian by winning further medals in Paris.

In a further controversy, an assistant coach and an analyst with the Canadian women's football team were sent home after rivals were spied upon.

The analyst, 43-year-old Joey Lombardi, was also given a suspended eight-month prison sentence for flying a drone over a New Zealand training session.

Lombardi pleaded guilty when he appeared in court in Saint-Etienne on Wednesday, the court told AFP.

The assistant coach was Jasmine Mander, to whom Lombardi reported.