This video can not be played Video shows scale of flash flood hitting Nepal-Tibet border The dramatic footage was almost impossible to miss. A torrent of water tearing through Gyirong Port, one of the main border crossings between Nepal and Tibet, sweeping away all in its path as hundreds of people fled for their lives.

The scenes, captured Only a single still-frame shot has been broadcast so far It has also been difficult to find the video on China's heavily censored internet. It is just as hard to even find posts describing the flash flooding that has said hundreds of lives, with just as many still unaccounted for since Wednesday.

Core Findings and Detailed Timeline

Beijing has launched a massive rescue operation involving hundreds of emergency workers, which is continuing, and President Xi Jinping chaired an emergency meeting with authorities to co-ordinate efforts. But when you compare the country's internet content to what much of the world has been seeing online these past few days, China's firewall becomes more visible than ever.

Tibet, which Beijing annexed in the 1950s, had long resisted rule China has quashed protests over the years, sometimes violently, and has been accused of grave rights violations in the Buddhist region. It has labelled the exiled spiritual leader, the Dalai Lama, a separatist. That history means the very name Tibet draws China's censors.

Beijing's sensitivities are especially apparent at times likes this. There have been daily updates on the missing and the dead, and Beijing has also been posting updates on the rescue operations, as well as the dangers posed But there is little detail beyond that.

There are no accounts from survivors in Tibet, and almost no user-generated footage showing the deadly moments or their aftermath.

Broader Implications and Future Outlook

We are yet to hear from anxious families of those missing. Trying to contact people there is near-impossible during regular times. As a journalist who has covered North Korea, it has often been easier for me to contact interviewees in Pyongyang than it is in the Tibetan capital, Lhasa.

On Thursday night, as global headlines led on the devastation in a Himalayan valley, China's state broadcaster opened its main bulletin with the launch of Xi's new book, a selection of his "most important and fundamental works". Instead, we have to rely on state media, which has so far focused on incredibly dramatic rescue efforts.

Specialist search teams scaling mountains and cliff faces, or crossing raging rivers to try to get to the worst-affected areas. We don't yet know what happened afterwards, or who they were able to save. This is not to say that Beijing is unconcerned.

Rather, they are very concerned. China's Premier Li Qiang was quickly despatched to the region, where he was seen inspecting debris removal - a rare visit The reason for what the world might see as a muted response is to preserve the one thing Xi covets for his country: stability.

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The Communist Party will fear that such a disaster could fuel discontent, either with the response or the lack of foresight to prevent it.

It may also fear the impact of a tragedy like this and its potential to be a rallying factor, especially in a community where faith has long played a central role. Although the region has not seen protests in a long time, Tibetan groups abroad have expressed concern over increasing Chinese control, such as new education laws that they say aim to weaken the role of monasteries and the Buddhist faith.

A notice came from the local party office urging members to step up and help in disaster relief efforts in their area and provide emotional guidance or psychological support to affected residents. The key line instructs them to "make every effort to maintain social order and ensure stability and public confidence in the disaster areas".

Those who perform well would be rewarded - and those who do badly "would be held accountable". It is a warning that will not be taken lightly. Tibetans in the region can be detained or arrested for speaking to journalists or posting anything online that is seen as contrary to the government narrative, according to rights activists.

That is making it difficult for Tibetans outside the region to find out what has happened to their relatives. To try to understand what life is like for Tibetans, the BBC travelled to a town that sits on the edge of the Himalayan plateau last year - just outside what China calls the Tibetan Autonomous region.

There, we spoke to monks at the Kirti monastery in Aba, or Ngaba in Tibetan, which was once at the heart of its resistance to Beijing. "We Tibetans are denied basic human rights," one monk told us. They shared they lived under constant surveillance and said the Chinese government oppressed and persecuted Tibetans.

The conversations were brief because we could not be seen speaking to anyone for long. Beijing denies it is violating Tibetans' rights, and points to the heavy investments it has made in the region to boost tourism and integrate it with the rest of the country.

Nevertheless, people in China will not know very much about what is happening in Tibet right now.

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