The police of Thailand on Sunday fired a burst of water cannons at thousands of pro-democracy protestors who marched to the Grand Palace in Bangkok to demand restrictions on King Maha Vajiralongkorn’s powers and the removal of the government, Reuters reported.

The Bangkok authority’s emergency unit said one police officer and four protestors were hurt during the brief confrontation outside the palace, where police had set a barricade of buses and barbed wire to stop demonstrators from proceeding.

Officers used the cannon for only the second time during the months-long protests to demand the departure of Prime Minister Prayuth Chan-ocha, a former junta leader who seized power in a 2014 coup. Police spokesperson Kissana Phathanacharoen said water cannon had been fired on Sunday “only as a warning”.

In a statement addressed to King Maha Vajiralongkorn, protestors said he should listen to “fearless criticisms”, as well as to flattery and praise. “When you hear all the flattering praise from the people, you must also hear fearless criticisms and suggestions all the same,” said the statement, signed “with power of equal human dignity” by “people”.

Thailand’s lèse-majesté law forbids the insult of the monarchy, and is among the strictest in the world, according to BBC.

Reuters estimated that more than 10,000 protestors marched from Democracy Monument in central Bangkok. But the police put the number at 7,000. Demonstrators, who wore goggles and hard hats for protection, moved buses and removed barbed wire that had been used by police to block access to the palace, according to The Guardian. They carried mock letterboxes, made from old rubbish bins and addressed to the Bureau of the Royal Household, to hand-deliver letters urging for reforms.

Police use water cannons as demonstrators march to The Grand Palace to hand letters written to the king, as part of a rally to call for the ouster of Prime Minister Prayuth Chan-ocha's government and reforms in the monarchy in Bangkok, Thailand, November 8, 2020. (Credit: Soe Zeya Tun/ Reuters)

Meanwhile, several dozen royalists earlier held a counter-protest at Democracy Monument, wearing yellow shirts in the colour of the king and waving Thai flags. Many held up pictures of the king and his late father, King Bhumibol Adulyadej.

Last month, the Thailand government had arrested many prominent protest leaders and announced a ban on gatherings of more than five people using an emergency decree. The protests have been going on since July.

The protestors’ demands include revoking laws against defaming the monarchy, a new constitution, abolishing royal offices, ousting the military-led government and disbanding the king’s royal guards. The protestors have also called for an end to intimidation of government critics.