The Tibetan community in Nepal called off plans to mark the birthday of their spiritual leader the Dalai Lama after their request for a public celebration was rejected over security concerns, a government official said on Sunday.

The Dalai Lama turned 84 on Saturday and his followers in Nepal had hoped to celebrate the occasion in the capital, Kathmandu, but the communist government rejected their request.

China, which regards the Dalai Lama as a dangerous separatist, has been increasing its influence in the Himalayan nation that is home to about 20,000 Tibetans.

Nepal is a natural buffer between China and India and is considered by New Delhi as its natural ally, but China is also making inroads by pouring aid and infrastructure investment into what is one of the world’s 10 poorest countries.

Beijing sent troops into remote, mountainous Tibet in 1950 in what it officially terms a peaceful liberation and has ruled there with an iron fist ever since.

The Dalai Lama fled to India in early 1959 after a failed uprising against Chinese rule.

Krishna Bahadur Katuwal, assistant district administrator of Kathmandu, said the government refused permission for Tibetans to mark the Dalai Lama’s birthday because “infiltrators” could create trouble.

“There could be a law and order problem as infiltrators could organise demonstrations or try to self-immolate,” Katuwal told Reuters.

Tibetan news portal Phayul.com said celebration plans were then withdrawn.

Airport immigration authorities in Kathmandu refused to admit a U.S. citizen of Tibetan origin and deported him last month, reportedly at China’s request.

Nepali authorities have also previously detained Tibetans trying to cross the border on their way to India after fleeing their disputed homeland.

Human rights groups say Nepal faces intense Chinese pressure to control the flow of Tibetans crossing the border.