Hacktivist group Anonymous issued a message over the weekend calling on the Iranian people to rise up and rebel against the Islamist regime, and pledged to provide any assistance they could. The message followed reports that Iran has cut off large swathes of the Internet, shutting down access to sites like Google and Youtube. And, experts said, the latest blockages could be the beginning of a long-promised plan by Iranian authorities to replace the general Internet with an Iranian “national internet,” which would conform to Islamic principles.

While Iran has tried to block access to Internet sites in the past, the latest blockages were far more intense, reported by Payvand News, an English-language website that reports news about Iranian dissidents. According to the site, the shutdown seemed timed to prevent Internet communication in advance of the February 14 anniversary of protests against the Iranian regime. The “Day of Rage” protests in 2011 that began that day lasted for more than a month, resulting in at least three dead and hundreds jailed. Iranian dissidents have been hoping to repeat the protests this year. Iranian authorities were apparently hoping to quash communications between protesters with the blockage, preventing them from coordinating protests and exchanging information.

Anonymous, a hacking group that has protested against Internet censorship around the world, issued a message as word of the blockage spread. The message, addressed to “the brave and noble people of Iran,” decried the suffering of Iranians at the hand of Iranian President Mahmoud Ahmedinejad.

“Ever since the Islamic Revolution in 1979, the Iranian People keep on trying to get rid of this Regime that is responsible for so much pain and sorrow in Iran, Palestine, Iraq, Syria, Lebanon and many other Countries throughout the World,” the message said. “Brothers, sisters, fathers, mothers and friends that have been unrightfully detained, tortured and murdered in several Iranian Prisons.

“This is not what Iran deserves. Iran deserves free elections, modern energy infrastructure and the will of its people to be listened to and carried out. We are neither employees of the CIA. We will support and fight for the Iranian People.”

Other groups marshaled their efforts to enable Iranians to outwit the authorities. Members of the Tor Project, which provides software that allows users to “spoof” (hide) their IP addresses, fooling servers into thinking that users are connecting from different locations, said they were setting up a special emergency “bridge” to override the increased filtering by Iranian authorities. Iran had already blocked access to some Internet sites, but Tor software had been able to run around those filters. In the past few days, however, Iranian authorities increased their filtering, and the number of users who have been able to connect to banned Internet sites with Tor software had fallen dramatically. Tor project members said they were working “around the clock” to come up with update software to beat the latest Iranian blockages.

Meanwhile, experts speculated that  the blockages were related to Iran’s plan to shut the country off from the general Internet, and implement a “national internet,” in which only government-approved sites would be allowed to operate. Iran, which has been working on the project since at least 2005, said that its “clean web” project was aimed at protecting Iranians from “the loose commitment to ethics and morality across the World Wide Web.” Iran’s Minister of Communications and Information Technology Reza Taqipour was quoted as saying that “the starting point of a clean web will be Iran and then it will be offered to all humanity.”

Among the features of Iran’s internet will be the implementation of its own search engine, called “Ya Haq,” which will be accessible from within Iran and will be able to reach only approved sites. The target date for the implementation of the search engine, set last June, is this month, and experts said that the disabling of access to Google could lead to a replacement of the worldwide search engine with the homegrown Iranian version.