By Hannah Beech and Muktita Suhartono

BANGKOK — Thai authorities shut down parts of Bangkok’s commercial centre and crippled public rail networks over the weekend in an effort to prevent young demonstrators from continuing their antigovernment protests.

It didn’t work.

Tens of thousands of members of the pro-democracy movement, which has been galvanized by a political awakening among social media savvy students, gathered in Thailand’s capital and in about 20 provinces Saturday (17) and Sunday (18) to call for fresh elections, a new Constitution and reforms to the monarchy’s lofty position in Thai society.

“I wasn’t always politically active,” said Perakarn Tangsamritkul, 23, who participated in one of several rallies in Bangkok on Saturday. “You should have met me three months ago. Now I understand why we have to be here. We have to speak out.”

Over the past few days, Thailand’s military-linked government, led by Prayuth Chan-ocha, a retired general who orchestrated an army coup in 2014, has intensified efforts to snuff out the months-long protests. But the calls for change appear to have gotten only stronger, making once-taboo political sentiments suddenly commonplace.

And in a country divided for decades between hostile factions — broadly, an urban elite and a rural base that has long felt ignored as Thailand’s wealth gap has grown — the current pro-democracy movement has transcended the traditional political rifts.

A 30-year-old civil servant who attended a rally at Victory Monument in Bangkok on Sunday said that he was gratified that the young generation had the courage to come out. He declined to provide his name given his government job, but said that he and the student protesters were united in the belief that the country had to change.

For years, Thais would elect populist leaders, only to see them removed by military coups or judicial manoeuvres that were approved by the palace. The country’s political old guard argued that the elected prime ministers were corrupt and adept at milking the system, charming the masses with promises of cheap health care and crop subsidies.

According to the country’s entrenched political elite, some of those elected leaders also challenged the authority of the constitutional monarch by positioning themselves as rivals in popularity to the king.

On Saturday, hundreds of doctors, some from hospitals known to be managed by royalists, signed a letter against the water cannons used to forcibly disperse protesters the day before. The water was laced with a chemical irritant, and the sight of students fleeing riot police shocked many Thais.

Hours later, Dr. Jarosdao Rimphanitchayakit, a surgeon, was fired for having her name among the 386 doctors.

“Mongkutwattana Hospital has a clear policy of not accepting those who are part of the enemy movement,” said Maj. Gen. Rienthong Nanna, the hospital director.

Thai authorities have built a formidable legal structure to try to criminalize the movement. On Thursday (15), the government issued an emergency decree in which public gatherings of more than four people were banned in the Thai capital, an order that has been ignored. With their emergency powers, the police can also declare any place in Bangkok off-limits to protesters.

Each day, the authorities detain more protest leaders, a whack-a-mole approach that has spurred new organizers to come forward. Thai Lawyers for Human Rights said that more than 80 protesters have been arrested over the past five days.

On Sunday, the police warned that posting a selfie from the protests on social media could lead to two years in prison. So could checking in online from a protest site.

“It is like you are taking your own evidence of disobeying the emergency decree,” said Maj. Gen. Yingyos Thepjumnong, a spokesman for the Royal Thai Police.

But Thailand’s political rebellion will be posted on Instagram and Facebook.

Protesters have formed online alliances with pro-democracy forces in places like Hong Kong. Activists from as far away as Nigeria and Belarus have sent millions of well-wishes online. One Thai K-pop fan club raised about $25,000 for supplies through online donations.

Over the weekend, the largely leaderless crowds in Bangkok took inspiration from their counterparts in Hong Kong, where protesters spent months honing their tactics for peacefully confronting a police force armed with tear gas, water cannons and rubber bullets: umbrellas, goggles and invocations to “be like water.” They also followed the strategy of waiting until the last minute to announce protest sites, to try to outwit the riot police.

Amid an occasional drizzle over the weekend, Thai protesters formed orderly lines to pass down helmets and raincoats to those closer to the front lines. With the telecommunications signal weakening, they took to yelling news and instructions down the protest columns instead.

On Sunday, a government spokesman said that while Prayuth was committed to listening to problems from all sides, he was also alert to any protesters who might incite violence. Thailand has suffered numerous violent crackdowns on protesters in the past, most recently in 2010 when dozens were killed in Bangkok as demonstrators were forcibly cleared from the streets.

Parliament has been warned to stand by for a special session Monday (19). The legislature was otherwise not scheduled to meet until November.

Far more incendiary than calling for Prayuth’s exit are the protesters’ demands that the king, one of the world’s richest monarchs, must hew to the Constitution rather than floating above it as a semi-divine being.

Thailand abolished absolute monarchy in 1932, but the crown retains an exalted status and is protected by strict laws criminalizing any disparagement. On Friday, two protesters were charged with committing “an act of violence against the queen’s liberty” after they had yelled in surprise at a passing royal motorcade in Bangkok two days earlier. If convicted, they could serve life in prison.

King Maha Vajiralongkorn Bodindradebayavarangkun, his queen and the heir apparent live mostly in Germany, even as the king has expanded his control over the crown’s finances and military units. The protesters have stressed that they are not looking to topple the king; they chanted “reform the monarchy” by the thousands on Sunday.

The day before, protesters took turns posing in front of a spray-painted sign on a road that showed the Thai flag superimposed with the words “Republic of Thailand.” The country is officially a kingdom.

At first, the demonstrators, despite their identities being obscured by face masks or helmets, posed quickly for selfies before darting away nervously. But soon they lingered, raising their arms in the three-fingered salute that has become a hallmark of the protests.

One young man stomped on the word “king” written near the flag. Members of the crowd gasped. Then they started to clap.

-New York Times