Gmail has been comprehensively blocked in China six months after government censors first began disrupting access to the service. Google’s Transparency Report shows Gmail traffic falling dramatically in the country on the night of December 25th, and while Chinese officials have not claimed responsibility, a Singapore-based spokesperson for Google told Reuters: "We've checked and there's nothing wrong on our end."

Chinese censors began disrupting Gmail access in May this year

China already blocks an array of Google services including its main search site, Google Maps, Google Docs, and Google Drive. The country began making access to Gmail more difficult in the run up to the 25th anniversary of the 1989 June 4th Tiananmen Square protests, but determined users could still access their accounts from apps via IMAP, POP, and STMP protocols. Now, it seems, Chinese censors have closed this loophole, leaving virtual private networks (VPNs) as the last remaining access route to Gmail and other blocked services.

Google data shows Gmail traffic in China falling sharply on the night of December 25th (Google)

China has been seen as taking an increasingly restrictive approach to online censorship in recent years, with one expert describing it as "an unprecedented crackdown." As well as Google, sites including Facebook, YouTube, and Twitter are all blocked in the country, while authorized services are heavily monitored and controversial search terms banned outright. Blocking Gmail however will not just hurt freedom of speech — it could also damage Google’s marketshare in countries that regularly do business with China. A member of censorship watchdog GreatFire.org told Reuters: "Imagine if Gmail users might not get through to Chinese clients. Many people outside China might be forced to switch away from Gmail."