The Eygptian government's crackdown on protestors intensified Friday with access to most forms of mass communication, including the Internet, mobile and SMS down, even as United Nations Secretary General Ban Ki-moon warned that "freedom of expression should be fully respected."

As the country braced for huge anti-government protests on the traditional day of prayer, the government appeared to have unplugged most means of communication--including social network Facebook and Twitter--that activists had been using to coordinate action across the country.

Landline calls placed from outside the country, however, were connecting.

Government-owned Telecom Egypt runs the country's fixed-line network.

In a blog, U.S.-based internet intelligence firm Renesys recorded how late Thursday it saw "the virtually simultaneous withdrawal of all routes to Egyptian networks in the Internet's global routing table," in what it called "an action unprecedented in Internet history."

Attempts to connect to the websites of several Egyptian ISPs, including EgyptWeb, TeData and Purenet all failed.

Renesys contrasted the scale of the crackdown with the "modest Internet manipulation that took place in Tunisia, where specific routes were blocked, or Iran, where the Internet stayed up," but download times were slowed.

During the rallies in Iran in 2009, one account from a person in the capital, Tehran, said it took 20 minutes to download Yahoo's website and that landlines, satellite phones and SMS were all disrupted.

And in 2007, security forces in Myanmar cracked down on communications following monk-led protests against the regime there, disabling some mobile phones and closing some service providers, but images of the clampdown continued to be relayed out of the country via cellphones. More than 110,000 people joined the Support the Monk's Protest in Burma group on Facebook.

In an emailed statement, Facebook said: "We are aware of reports of disruption to service and have seen a drop in traffic from Egypt since Thursday," while Twitter wasn't immediately available to comment on what is happening in Egypt.

Meanwhile, U.K.-headquartered Vodafone Group PLC (VOD) said in a statement that all mobile operators in Egypt had been "instructed to suspend services in parts of Egypt. Under Egyptian legislation, the authorities have the right to issue such an order and we are obliged to comply with it."

It said the Egyptian authorities will be clarifying the situation in due course.

Vodafone Egypt, the country's largest operator by customers, competes with Egyptian Co. for Mobile Services (EMOB.CI), also known as Mobinil, and Etisalat Egypt, a subsidiary of United Arab Emirates-based Emirates Telecommunications Corp. (ETISALAT.AD)

France Telecom (FTE) and Orascom Telecom (ORTE.CI) last year reached a settlement over the ownership of Mobinil.

France Telecom also confirmed that the Egyptian authorities had taken "measures to block mobile phone services," and apologized to Mobinil customers, adding it had no information about when service would be restored.

All attempts to reach other mobile and Internet operators in the country were unsuccessful either because offices were closed due to the weekend or because mobile numbers weren't working.

"From my knowledge of the region, I suspect the Egyptian government controls the main ISP in the country and would thus be able to decouple the main backbone in Egypt from the rest of the Internet," said Sean Sullivan, security advisor at Finnish IT security firm F-Secure. Sullivan drew paralles with Syria, where the government also has full control of the Internet backbone and can therefore shut down the network if it wishes.

"It's a blunt instrument to fight what is happening" in Egypt, Sullivan said, referring the communications clampdown, but people in the country seemed to be finding alternatives to get news out to the world, for example via satellite connections or by placing calls to friends who then tweet for them.

According to Egypt's National Telecom Regulatory Authority, or NTRA, mobile subscribers in the country reached 53.43 million by the end of the third quarter of 2010, the latest figures available.

Earlier this week, blogs and social networks were full of calls to take to the streets to bring down the regime of Egyptian President Hosni Mubarak.

Egypt's Interior Ministry had warned it would take decisive measures against the protestors in the Arab world's most populous nation, after organizers said demonstrations set to take place after noon prayers Friday would be the biggest in decades.

The protests in Egypt after the 25-year regime of Zine El Abidine Ben Ali was toppled in Tunisia, sparking shockwaves across the Arab world.

Speaking at the World Economic Forum in Davos, Switzerland, UN Secretary General Ban Ki-moon warned that "freedom of expression should be fully respected" in Egypt.

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