On top of a giant yellow inflatable duck, a rebel Buddhist monk in saffron robes displayed a defiant three finger salute at a pro-democracy protest in central Bangkok.

Scores of the pool toys bobbed through a crowd some 20,000 strong on Wednesday as activists descended on the Thai national police headquarters to throw paint and scrawl obscene anti-royal slogans on the streets.

Yellow inflatable ducks are fast becoming a symbol of the Thai pro-democracy protests
Yellow inflatable ducks are fast becoming a symbol of the Thai pro-democracy protests AFP / Jack TAYLOR

The cute yellow birds are fast becoming a symbol of the Thai protests after demonstrators used them a day earlier as shields against the burning spray of police water cannon and tear gas at a rally near parliament.

Tuesday saw the most violent confrontations since the rallies kicked off in July -- six people were shot during scuffles between royalists and democracy activists.

The youth-led movement is demanding a new constitution, making unprecedented calls to reform the untouchable monarchy, and for the resignation of Prime Minister Prayut Chan-o-cha, who came to power in a 2014 coup.

A protestor walks with an inflatable duck during a rally in Bangkok. Inflatable ducks have also featured in protests in Brazil and Russia
A protestor walks with an inflatable duck during a rally in Bangkok. Inflatable ducks have also featured in protests in Brazil and Russia AFP / Jack TAYLOR

Footage of Thailand's so-called "rubber duck revolution" has gone viral on social media this week.

"If the politics are good, ducks will only be used in the pool," one Twitter user remarked.

The ducks have become a symbol of the Thai protests after demonstrators used them as shields against police water cannon
The ducks have become a symbol of the Thai protests after demonstrators used them as shields against police water cannon AFP / Jack TAYLOR

"Here you go, the most terrifying weapon from the protesters' side: an inflatable duck," a Facebook user wrote.

"Duck is a fighter, no matter how much people bully him, he still keeps smiling," a Thai man tweeted alongside a picture of a battered and slightly deflated duck.

The duck protest appearances have also inspired a bevy of artwork.

Thailand's 'rubber duck revolution' is calling for a new constitution, reforms to the monarchy and the resignation of Prime Minister Prayut Chan-o-cha, who came to power in a 2014 coup
Thailand's 'rubber duck revolution' is calling for a new constitution, reforms to the monarchy and the resignation of Prime Minister Prayut Chan-o-cha, who came to power in a 2014 coup AFP / Jack TAYLOR

Thai artist Wannasin "Matthew" Inpin used a tablet computer to whip up a cartoon of a part-duck part-strong man figure protecting protesters.

"Rubber ducks are very fragile and I think it is not a fair fight at all but I think this act shows the protesters' fearlessness and strength to fight back," he told AFP.

"That's why I drew the duck as a strong animal who protects protesters and is not afraid of dictatorship."

The inflatable pool ducks are retailing on Lazada Thailand, an online shopping portal, for 499 baht ($15).

It's not the first time the bathtime buddies have been used as symbols of defiance and protest.

In 2013 Dutch artist Florentijn Hofman's 16-metre inflatable duck sculpture floated in Hong Kong's harbour but swiftly became mired in controversy.

A Weibo user edited a famous image from the 1989 Tiananmen Square crackdown, replacing tanks with ducks prompting a Chinese government internet search ban on "big yellow duck".

Giant inflatable rubber ducks featured in protests in Brazil in 2016 during a push to impeach then-president Dilma Rousseff and highlight the economic "quackery" of her government amid a downturn.

And they also became a symbol of protest in Russia in 2017 when it emerged then-prime minister Dmitry Medvedev had multiple luxury estates including one that featured a special house for ducks on a pond.

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