Footage of a Samoan flag being burned has sparked fury following Tonga's dramatic Rugby League World Cup victory over their Pacific rivals, prompting calls for a public apology from the Tongan government.

Tonga defeated Samoa 20-18 at CommBank Stadium in Parramatta on Sunday, with Addin Fonua-Blake scoring the match-winning try in the 73rd minute of a bruising encounter.

The result sent Tonga into a semi-final against New Zealand, while Samoa advanced to face Australia. Both nations remain in contention for the trophy, meaning their fiercely contested clash could be repeated in the World Cup final.

The fixture is among international rugby league's most passionate, with Tonga's Sipi Tau and Samoa's Siva Tau setting the tone for a rivalry fuelled by national pride, cultural connections and enormous support across Pacific communities.

But now footage has emerged of two young people burning a Samoan flag after the game. It has drawn widespread outrage, with young fans urged to respect their neighbours regardless of the result.

The video showed two children setting fire to a Samoan flag, with the caption Tokoua koe kau toa koaa – you are the only heroes – and three laughing emojis.

Facebook user Aloisia Tuukaelaua Vake, who described those involved as Tongan children, demanded action from their parents and called for the government to apologise.

'Tongan parents, please raise your children properly. They should never be disrespectful towards any country's flag, no matter what,' she wrote.

'I woke up to see a video on social media of two Tongan children burning the Samoan flag after the games last night, and it made me furious.

'This behavior is absolutely disrespectful and disgusting. I believe there should be serious consequences for such actions.'

Vake said the incident reflected badly on Tonga and called for a public response.

'The Tongan government and the parents of these children should make a video to apologize to Samoa,' she wrote.

Other commenters condemned the act while appealing for unity between two nations whose sporting rivalry is matched by close family and community ties.

'It's truly disappointing to see this happen. A flag deserves respect, no matter which country it represents,' one wrote.

'However, please don't let the actions of a few children divide our beautiful Pacific family.

'Tonga and Samoa share more than just an ocean - we share history, blood, and deep love. Let's teach respect, not create more division.'

Another said adults had a responsibility to ensure children understood the difference between supporting their country and disrespecting another.

'Respect for every nation and its flag should be taught from a young age,' they wrote.

'Children need guidance, discipline, and good examples from adults. We can be proud of our own country while respecting others.'

One commenter pointed to the generations of people represented by a national flag.

'Burning a flag doesn't diminish the country or erase its history. It only reveals the level of disrespect of the person setting it on fire,' they wrote.

Perhaps the strongest response came from a supporter identifying as Samoan, who described stopping beside a busy highway to retrieve a fallen Tongan flag.

The commenter said they were driving to collect their daughter from work when they spotted it, stopped and picked it up.

Believing the flag had fallen from a family's car, they folded it and placed it on their dashboard.

They then pledged to fly it alongside their Samoan flag on the roof of their ute.

'Win or lose we gotta learn to respect other nations,' they wrote.

The anger follows a match that also demonstrated the extraordinary appeal of the Tonga-Samoa rivalry.

The game drew the largest crowd for any sporting event at the new Parramatta Stadium, while supporters staged pre-game parades as far away as Houston, Salt Lake City and San Francisco.