Laser show lights up Tahrir Square

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STORY: Protesters thronged Cairo's Tahrir Square, cheering loudly as an anti-government laser show lit up the square. A quarter of a million packed the square after work, celebrating wildly what they believe is Egyptian President Mohamed Mursi's impending departure.

Senior Muslim Brotherhood leaders branded the military ultimatum a "coup", backed by a threat that the generals will otherwise impose their own road map for the nation.

The Brotherhood's political wing called for mass counter- demonstrations to "defend constitutional legitimacy and express their refusal of any coup", raising fears of violence.