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China has been cracking down on virtual private networks, which enable people to get around the country's infamous internet filter dubbed the Great Firewall. Now, Apple is removing VPN apps from its China App Store.

ExpressVPN said Saturday it received a letter from Apple saying its iOS app was taken down. The reason for the removal? "It includes content that is illegal in China, which is not in compliance with the App Store Review Guidelines," the letter states. The news was reported earlier by The New York Times.

Zhang Peng

ExpressVPN said in the blog post that after some initial research it found "all major VPN apps for iOS have been removed." In a tweet, Star VPN on Saturday also said it received a notice from Apple.

Responding to a request for comment, Apple said the country's Ministry of Industry and Information Technology earlier this year "announced that all developers offering VPNs must obtain a license from the government." China's MIIT regulates the internet and wireless industries, among others. "We have been required to remove some VPN apps in China that do not meet the new regulations," Apple added. "These apps remain available in all other markets where they do business."

ExpressVPN called Apple's move "surprising and unfortunate."

"It represents the most drastic measure the Chinese government has taken to block the use of VPNs to date, and we are troubled to see Apple aiding China's censorship efforts," the company said in the blog post. "ExpressVPN strongly condemns these measures, which threaten free speech and civil liberties."

Using VPNs is one of the ways that people inside China are able to access news and social media sites -- such as The New York Times, Twitter and Facebook -- that have been banned by the government. Earlier this month, China reportedly ordered three state-run wireless carriers to block people from accessing VPNs by February 1.

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