Google Maps has found itself in a bit of a kerfuffle on social media after some users noticed that some of its maps highlighted the controversial so-called nine-dash line that marks China’s claims over the South China Sea.

On Twitter, several China watchers pointed out Google Maps images of long dashes near Taiwan and the Philippines. One Twitter user wrote to @googlemaps, “Hello. Was there a recent maps update to officially recognize the 9/10 dash line in #SouthChinaSea?”

The nine-dash line was rejected this summer by an international tribunal, which said China couldn’t use it to claim historic rights to most of the South China Sea.

Google left China in 2010 after disagreements with Beijing over censorship. Google search and Google Maps are blocked in China, though local domains exist for both Google.cn and maps.google.cn and many users in China access the local and global versions via virtual private networks to get around China’s Great Firewall.

Google Maps has said it abides by local law, meaning that disputed territories would appear in local domains to show sovereignty, but not on global domains. By this logic, the nine-dash line would only be seen on maps.google.cn, and not maps.google.com. A China Real Time test showed that the line did appear via the local domain, but not a global maps domain.

Similarly, on a Google India map, Jammu and Kashmir are clearly defined with regular borders, while they appear within dots on the global Google Maps.

As of Tuesday afternoon, Google hadn’t issued a statement on the matter.

Google Maps’ use of the nine-dash line isn’t new, according to one person familiar with the matter, though the person indicated it could have been added fairly recently, potentially with the latest update from a third-party provider.

Google Maps receives significant amounts of data from third-party providers. Its main provider in China is AutoNavi Holdings Ltd., which was acquired by Alibaba Group Holding Ltd. two years ago. A call to AutoNavi wasn’t immediately returned.

Last year, a third-party data provider to Google labeled parts of the South China Sea with the Chinese name of Huangyan Island on maps appearing globally instead of the international name of Scarborough Shoal, prompting an online petition in the Philippines. Google Maps removed the Chinese name, saying in a statement that it understood that “geographic names can raise deep emotions, which is why we worked quickly once this was brought to our attention.”

Google also challenged the South Korean government earlier this year over national- security restrictions that it says makes some of its maps less informative than those for North Korea.

—Alyssa Abkowitz. Follow her on Twitter, @AlyssaAbkowitz