Customs authorities in China in the coastal province of Shandong have intercepted 60,000 maps that "improperly identified" the self-ruled island of Taiwan, which Chinese authorities considers part of its sovereign land.
The maps, customs representatives explained, also "omitted important islands" in the disputed South China Sea waters, where China's territorial assertions conflict with those of its regional neighbors, including the Philippines and Vietnamese authorities.
The "non-compliant" maps, c intended for foreign distribution, cannot be sold because they "threaten national unity, sovereignty and territorial integrity" of the People's Republic of China, officials confirmed.
Cartographic materials are a sensitive topic for China and its rivals for reefs, islands and outcrops in the South China Sea.
Customs authorities explained that the maps also did not contain the nine-segment line, which demarcates Beijing's claim over almost the whole South China Sea.
The line comprises nine dashes which runs a significant distance south and east from its most southerly province of Hainan.
The seized maps also omitted the maritime boundary between China and Japan, authorities said.
Officials stated the maps incorrectly labeled "the Taiwan region", without specifying what exactly the improper identification was.
The Chinese government sees self-governed Taiwan as its territory and has kept open the possibility of the use of force to take the island. But Taiwanese authorities views itself as distinct from the Chinese mainland, with its own constitution and democratically-elected leaders.
Conflicts in the disputed maritime region sometimes intensify - just recently over the weekend, when vessels from Chinese authorities and the Philippine government figured in another encounter.
Philippine authorities alleged a China's maritime craft of deliberately ramming and deploying water jets at a official Philippine ship.
But Beijing stated the incident happened after the Philippine vessel disregarded multiple alerts and "came too close to" the Chinese vessel.
The Philippines and Vietnamese authorities are also highly vigilant to portrayals of the South China Sea in cartographic materials.
The popular motion picture from 2023 was prohibited in Vietnam and edited in the Philippine release for showing a maritime chart with the nine-segment boundary.
The announcement from customs authorities did not specify where the intercepted items were planned for distribution. The country provides much of the global merchandise, from holiday decorations to stationery.
The confiscation of "violating charts" by customs officials is relatively common - though the amount of the maps intercepted in the Shandong region easily eclipses previous confiscations. Goods that do not meet standards at the customs are disposed of.
In March, customs officers at an air transportation hub in the coastal city intercepted a shipment of 143 nautical charts that featured "clear mistakes" in the territorial boundaries.
In late summer, customs officers in the northern province intercepted two "violating cartographic materials" that, among other things, contained a "misdrawing" of the the Tibet region's limits.