BEIJING — A court in Kazakhstan convicted 19 activists after a protest against Beijing’s crackdown in China’s far-western Xinjiang region last year, in what experts and advocates said was the largest move yet by the Kazakh government to silence criticism at Beijing’s behest.

The activists, all of whom were Kazakh nationals, protested near the border with China in November, burning Chinese flags and portraits of Chinese leader Xi Jinping and calling for the release of a Kazakh citizen detained in Xinjiang last year.

Eleven activists were sentenced to five years in prison for “inciting discord,” while the other eight were given restrictions on their movement. Shinquat Baizhan, a lawyer representing the activists, confirmed the sentences, which were also reported in local media.

Though Kazakhs speaking out against China’s policies in Xinjiang have long faced pressure, advocacy groups say this is the first time such a large group of Xinjiang activists has been imprisoned in the country.

“This is unprecedented,” said Yalkun Uluyol, China researcher at Human Rights Watch. “It signals that Kazakhstan is willing to sacrifice freedom of its people to maintain good relations with Beijing.”

The Chinese government launched a brutal crackdown in Xinjiang starting in 2017, sweeping a million or more Uyghurs, Kazakhs, and other predominantly Muslim ethnicities into prisons and internment camps. Though many have since been released, the region remains under tight control, with strict limitations on religious and cultural practices.

Xinjiang has long been a touchy issue in neighboring Kazakhstan, a Central Asian country of 20 million people that relies on China as a major trading partner. The Kazakh government opened criminal investigations targeting the protesters after receiving a diplomatic note from the Chinese consulate in Almaty, Kazakhstan’s largest city, Uluyol said.

The note, which The Associated Press obtained and reviewed, called the protest “an open provocation against the national dignity of the People’s Republic of China and an insult to the Chinese Communist Party and the Chinese people.”

In a statement, the Chinese Ministry of Foreign Affairs called the sentencing an “internal affair” and praised Kazakhstan as a “friendly neighbor” that is “familiar with China’s policies on governing Xinjiang.”

The Kazakh Ministry of Foreign Affairs did not respond to a request for comment.

The protesters were members of Atajurt, an organization that advocates for the rights of Chinese-born Kazakhs facing repression in China. Xinjiang is home to over a million ethnic Kazakhs, thousands of whom were detained and many more who face restrictions on their movement to this day.

Atajurt has long faced pressure from the Kazakh government, an authoritarian state with little tolerance for dissent. Authorities arrested Atajurt’s founder Serikzhan Bilash in 2019, releasing him into exile after extracting a promise not to engage in political activities.

But the Kazakh government remained tolerant of the organization’s activities to a certain extent, mindful of widespread sympathy in Kazakhstan toward the Chinese-born Kazakh population,

That appears to have changed, Uluyol said, as Kazakhstan has edged closer to China and authorities in Kazakhstan show less tolerance for groups protesting Beijing’s policies.

Bilash, Atajurt’s founder, says the arrests would have widespread ramifications. The group’s work included providing financial support for the relatives of people who were detained in Xinjiang, writing letters supporting them to embassies and the United Nations, and taping hundreds of testimonies by people looking for missing loved ones.

“The world will lose more than just a human rights organization; it will lose the biggest window into the humanitarian disaster in neighboring Xinjiang,” said Bilash, who is now living in exile in the United States.