In the Tibetan regions ruled by China, one religious institute stands out — Larung Gar, in the county of Sertar. There, thousands of monks and nuns live in rows of cells that sprawl across the undulating hills. It has been described as the largest Buddhist institute on the planet.

But Chinese officials have begun demolishing many of the monastic homes, in another attempt to shape and control Tibetan culture and religious life, say representatives of two Tibetan advocacy groups outside China. The decades-old monastery, in northern Sichuan Province, is also a popular destination for Chinese Buddhists.

Demolition work began last week, and images of bulldozers and piles of rubble have circulated on social media, according to the International Campaign for Tibet, based in Washington. The lamas in charge of the institute have urged people in the area to stay calm, the group said.

“Larung Gar in Sertar has become increasingly prominent in both Tibet and China in recent years as a vital center for the study, practice and promotion of Buddhist teachings otherwise difficult to access or nonexistent in regular monasteries and nunneries due to restrictions put in place by the Chinese government,” the group said.