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.

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."

It 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.

Facebook and Twitter weren'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.

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.

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 come 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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