Previously, the Chinese-language edition of Wikipedia had been blocked, but now other editions of the online, user-generated encyclopedia are also inaccessible in China.
Internet researchers from the Open Observatory of Network Interference (OONI), which is run by a U.S.-based non-profit, said earlier this month that editions of Wikipedia in several languages had been banned as of April.
The ban came ahead of the 30th anniversary, on June 4, of deadly protests in Beijing’s Tiananmen Square.
The Chinese government regards the event as very politically sensitive and strengthens censorship every year around the date.
The Wikimedia Foundation, which runs Wikipedia, did not immediately answer questions emailed by dpa on Wednesday; however, the foundation earlier confirmed to the BBC that all language versions of its website have been blocked in China.
Wikipedia joins the ranks of Google, Twitter, YouTube, Facebook, WhatsApp, and others, which are locked behind China’s so-called “Great Firewall.”
The Chinese government has been running tight controls over the internet for years by censoring sensitive content and blocking access to foreign websites.
Google, the world’s largest search engine, left China in 2010 meanwhile is reportedly trying to re-enter the market by building a censored search app.
The websites of human rights groups and news organisations such as the New York Times and the Wall Street Journal are also banned in China.