HONG KONG — An American reporter for Buzzfeed News has become the latest foreign journalist to be forced from China, which has a history of retaliating against news organizations and individual journalists for critical coverage.

Megha Rajagopalan, who was Buzzfeed News’s China bureau chief, said it was not clear why China’s Foreign Ministry declined to issue her a new journalist visa. “They say this is a process thing, we are not totally clear why,” she wrote Wednesday on Twitter.

Ms. Rajagopalan has written extensively about surveillance and mass incarceration of ethnic Uighurs and other Muslim minorities in the Xinjiang region of northwest China, subjects the Chinese authorities have tried to block journalists from covering.

This month United Nations human rights experts confronted Chinese officials over estimates that one million or more Uighurs and other minorities were being held in re-education camps. Chinese officials denied the existence of the camps, saying instead that minor criminals were being assisted with rehabilitation.

The Foreign Correspondents’ Club of China said Ms. Rajagopalan’s visa denial was “extremely regrettable and unacceptable for a government that repeatedly insists it welcomes foreign media to cover the country.”

Ms. Rajagopalan was the first reporter for Buzzfeed permitted to work on a regular basis in China by the Foreign Ministry. The ministry and security agencies have traditionally not allowed online-only news publications to have reporters officially live in China.

But in recent years, several online-only news organizations have asked China to give residency status to reporters they wanted to post there. The authorities have responded by giving them temporary visas that are more easily revoked.

The Chinese government had told Buzzfeed it would allow Ms. Rajagopalan to stay in China on a visa that was valid for six months, and the visa could be renewed with the approval of officials. Ms. Rajagopalan’s visa was renewed once, but officials decided this spring not to renew it a second time.

This was the same system China set up several years ago for The Huffington Post, which, in coordination with WorldPost, wanted to station an American reporter, Matt Sheehan, to Beijing. Chinese officials granted Mr. Sheehan a renewable six-month visa, and Mr. Sheehan lived in Beijing until he decided to return to the United States.

The Huffington Post and Buzzfeed had de facto bureaus in Beijing, even if those existed under a system separate from the one under which traditional news organizations operated.

Traditional news organizations generally get a one-year renewable visa for their reporters residing in China and have bureaus officially recognized by the Foreign Ministry. But in recent years, Chinese officials have signaled that they may not renew those visas if reporters write articles that officials deem to be out of bounds.

In December 2015, Ursula Gauthier, a reporter in Beijing for the French newsweekly L’Obs, was denied a renewal of her standard one-year journalist’s resident visa. Foreign Ministry officials had criticized her for writing an article on the plight of Uighurs in Xinjiang. Global Times, a state-run nationalist newspaper, published at least one editorial criticizing her before she was forced to leave. No foreign journalist had previously been rebuked by Chinese officials in such a manner in many years.

After Bloomberg reported in 2012 about the wealth accumulated by the family of Xi Jinping, who became China’s leader a year later, the Foreign Ministry blocked all its applications for new journalist visas. The New York Times also had difficulty obtaining further residency visas for journalists after publishing stories in 2012 about how the family of Wen Jiabao, then premier, grew rich during his leadership.

On a trip to Beijing in late 2013, Vice President Joseph R. Biden Jr. criticized China over the use of visas to pressure foreign media outlets.

Ms. Rajagopalan lived in Beijing and worked for Thomson Reuters from 2012 to 2016. She left China after joining Buzzfeed in July 2016. Buzzfeed editors hired her with the aim of posting her to China, and she reported on Asia for Buzzfeed from Bangkok while the company negotiated with Chinese officials over a journalist’s visa. After China granted the six-month visa, she returned to Beijing in March 2017.

The United States State Department said in an email on Thursday that American officials would continue to raise concerns with their Chinese counterparts about restrictions on media freedoms.

The department’s response did not address the case of Ms. Rajagapolan or reply to a question on the broader issue of visa reciprocity — that is, whether the United States government should engage in tit-for-tat responses when the Chinese government denies visas to journalists.

The visa issue has been under serious discussion among American officials since the Obama administration. In Washington, officials are leaning toward taking harder measures against China on a wide range of matters, from trade to visas to the Chinese military’s actions in Pacific waters.

Ms. Rajagopalan said it was “bittersweet to leave Beijing after spending six wonderful and eye-opening years as a journalist there.”

She wrote that she was moving to a new position with Buzzfeed focusing on technology and human rights and reporting from the Middle East and elsewhere.

“I also want to make clear that though I can’t do it from inside China anymore, I’m not going to stop reporting on and speaking about state surveillance, repression and incarceration of millions of Muslim ethnic minorities in Xinjiang,” she added.

In a further sign of the Chinese government’s determination to suppress politically sensitive topics reported by foreign news organizations, the lawyer of a prominent Tibetan education advocate who was imprisoned after having spoken with The New York Times said Thursday that his client’s appeal had been denied.

The imprisoned advocate, Tashi Wangchuk, 33, an outspoken supporter of the right of Tibetans to study their own language, was sentenced to five years’ imprisonment in May on charges of “inciting separatism.”

The following month a United Nations human rights panel condemned the punishment and urged China to release Mr. Tashi immediately, saying he had been wrongly imprisoned over “his right to freely express his opinion about the human rights of the Tibetan minority of China.”

Mr. Tashi was arrested in early 2016 after he had given interviews to Times journalists, asserting that he did not support Tibetan independence but was simply in favor of greater use of the Tibetan language in schools across Tibetan regions of China.

Source: THE NEW YORK TIMES