India has issued a strong demarche to China after an Indian national from Arunachal Pradesh, Prema Wangjom Thongdok, was allegedly harassed by Chinese immigration officials at Shanghai Pudong Airport.

According to Indian officials, Thongdok was detained on what they described as “ludicrous grounds.” New Delhi reiterated that Arunachal Pradesh is an integral part of India and its residents are fully entitled to travel with Indian passports.

The Indian Consulate in Shanghai intervened immediately, providing assistance to Thongdok and raising the matter with local authorities. Officials said the actions of Chinese authorities violated international aviation regulations under the Chicago and Montreal Conventions.

Thongdok, an Indian citizen from Arunachal Pradesh residing in the United Kingdom, told ANI that she was singled out during a transit from London to Japan. She alleged that officials mocked her Indian citizenship, declared her passport invalid, and told her that “Arunachal is not part of India.”

“They laughed and said I should apply for a Chinese passport,” Thongdok said, adding that she endured an 18-hour ordeal before receiving help from Indian diplomats in Shanghai and Beijing. She also alleged humiliating behavior by China Eastern Airlines staff.

The incident comes amid ongoing high-level engagements between India and China aimed at strengthening bilateral ties. The Ministry of External Affairs has reiterated that attempts to rename places in Arunachal Pradesh do not alter the fact that the state “was, is, and will always remain an integral and inalienable part of India.”