WhatsApp being targeted by China's censors

Cyber experts say China's censors may be catching up with WhatsApp.

The WhatsApp servers in China weren't blocked but were "largely unavailable," said Charlie Smith of GreatFire.org, a group that monitors internet censorship in the country.

"I have also conducted speed tests from China and these sites are not reachable," he told CNNMoney.

Messaging app WhatsApp is owned by Facebook.

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