Tens of thousands of people are gathering in Egypt today in what is expected to be the biggest display of opposition to President Hosni Mubarak so far. The protests come amid a vast security clampdown. Police are firing tear gas into the crowds and have begun to round people up on the streets. A number of journalists have also reportedly been arrested, including some who have been badly beaten. There are also reports that Mohamed ElBaradei, the Nobel Peace laureate and former head of the U.N. International Atomic Energy Agency, has been arrested in Cairo. Earlier, the Egyptian government blocked internet, mobile phone and SMS services in order to disrupt the planned demonstrations. At least seven people have died and up to 1,200 have been arrested since the protests began. Arabic wire news services have reported that 1,000 activists were arrested in addition last night, and 149 have been charged with attempting to overthrow the government. Egyptian authorities have also arrested 20 members of the Muslim Brotherhood, including two of its most senior members. On Thursday, Muslim Brotherhood spokesperson Essam Al-Arian called the protests an “explosion” of popular resistance.

Essam Al-Arian: “We predict that closing the doors, rigging the elections for casting the worker syndicates and professional syndicates, preventing even students from choosing their student unions freely, that it will accumulate and accumulate and lead to explosion. We are facing the explosion.”