Chinese customs officers in eastern Shandong province have seized 60,000 maps that mislabelled the self-governed island of Taiwan, which Beijing claims as part of its territory.
The maps, authorities said, also omitted important islands in the South China Sea, where Beijing's claims overlap with those of its neighbours, including the Philippines and Vietnam.
The problematic maps, meant for export, cannot be sold because they endanger national unity, sovereignty and territorial integrity of China, according to authorities.
Maps are a sensitive topic for China and its rivals over various territories in the South China Sea.
China Customs stated that the maps also did not depict the nine-dash line, which outlines Beijing's claim over nearly the entire South China Sea. The line consists of nine dashes extending hundreds of miles from Hainan province.
Additionally, the seized maps failed to mark the maritime boundary between China and Japan. While exact details of the mislabelling of Taiwan province were not disclosed, the significance of such designations is evident.
Beijing sees self-ruled Taiwan as its territory and has not excluded the potential use of force to unify the island with the mainland. However, Taiwan perceives itself as distinct from China, possessing its own constitution and democratically-elected government.
Tensions in the South China Sea have escalated recently, including a reported incident over the weekend between Chinese and Philippine vessels.
The Philippines accused a Chinese ship of deliberately ramming and spraying water at a Philippine government vessel, while Beijing claimed the Philippine vessel ignored warnings and approached dangerously.
Both the Philippines and Vietnam have shown sensitivity to how maps portray the South China Sea due to their own territorial claims. For instance, the 2023 'Barbie' movie faced bans and censorship in these countries for depicting a map featuring the disputed nine-dash line.
The Chinese Customs did not specify where the confiscated maps were intended for sale. China is a major supplier for various goods globally.
Seizing so many problematic maps is unusual, with past instances being fewer in numbers. Generally, goods failing encounters at customs may be destroyed. Earlier in March, customs at Qingdao airport seized 143 nautical charts with obvious errors in national borders, and in August, customs in Hebei province confiscated two maps with discrepancies in the Tibetan border.