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 regarding reefs, islands, and outcrops in the South China Sea.

China Customs noted the maps did not contain the nine-dash line, which encompasses Beijing's claim over nearly the entire South China Sea. This line stretches hundreds of miles south and east from Hainan, China’s southernmost province.

Furthermore, the seized maps failed to delineate the maritime boundary between China and Japan.

Authorities indicated that the maps mislabelled Taiwan province, without specifying the inaccuracies in question.

Recognizing self-ruled Taiwan as its territory, China has not dismissed the possibility of using force to reclaim the island, while Taiwan defends its distinct identity with its own constitution and elected leaders.

Tensions denote the South China Sea, highlighted recently by an encounter where ships from China and the Philippines clashed. Manila accused a Chinese vessel of intentionally ramming and firing water cannons at a Philippine ship, while Beijing claimed the incident followed multiple warnings to the Philippine vessel.

In regards to geographical depictions, the Philippines and Vietnam are particularly sensitive, previously witnessing instances of censorship due to portrayals involving the South China Sea.

China Customs did not disclose the intended destination for the confiscated maps, although imaging this situation is not uncommon. It noted that goods failing customs inspections are often destroyed or seized.

Historically, such seizures include previous instances where customs in Qingdao confiscated 143 nautical charts with significant mapping errors and Hebei customs officers seized maps with inaccuracies concerning Tibet's borders.

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