Iran has blocked Internet access to https and drastically slowed down access to some http websites, practically cutting off access to Google and Yahoo. Gmail, a Google service, was also inaccessible to many Iranians. Accessing the Internet through virtual private networks (VPNs) seemed to be the only way to get through.
The censorship started on Saturday, the 33rd anniversary of the Islamic Republic, and is continuing today. There are unconfirmed reports that the government censors who control public access to the Internet through a national firewall were concerned of Internet communications related to possible opposition rallies in the coming days.