China has blocked one of the few Western social media sites that had remained accessible to its population: Pinterest.

The site has followed the example of Facebook, Twitter and many others after the photo sharing site was blocked in China, according to data from censorship monitoring organization GreatFire. GreatFire checks a range of the internet’s top websites for accessibility in China on a regular basis, and its system noted that Pinterest.com has been unavailable in China for the past seven days.

The Great Fire Wall, China’s internet censorship system, is prone to glitches and temporary blocks, but the fact that Pinterest has been inaccessible from China for a week now suggests that it has been very deliberately censored. Which brings us to the question of which a site that is famed for sharing images of animals, wedding dresses, recipes and other photos would be targeted by the Chinese government and deemed unfit for purpose in the country.

Pinterest is not exactly a mainstream service in the country, a number of clones sprouted up in China when the U.S. service struck out in 2012, but the block is significant as it represents one of the few popular Western social media sites that was freely accessible in China. It’s not exactly clear why the site is being blocked, but it could well be related to timing. ‘Two Sessions,’ the annual gathering of China’s governing classes, is taking place right now in Beijing which puts the government on high-alert for potential problems. Pinterest, it seems, had caught the eye.

We contacted Pinterest for comment and will update this post with any response we get.