Arab satellite network Al Jazeera has reported that Egyptian opposition leaders plan to negotiate a transition government with the Egyptian army, which maintained a heavy presence throughout the country on Sunday, and not longtime President Hosni Mubarak.

Al Jazeera reporters blogged that protesters still crowded Cairo's Tahrir Square after 11 p.m. Sunday, calling for Mubarak to resign. At one point, protesters spelled out "Down with Mubarak" with their bodies, the network reported.

Heavy machine-gun fire could be overheard Sunday night as thousands of protesters marched through downtown Alexandria, CNN's Nic Robertson reported. Army troops were positioned in various parts of the port city, having moved some of their checkpoints over the weekend.

Maajid Nawaz, executive director of the Quilliam Foundation, a London-based think tank, told Al Jazeera that Mubarak was a liability to political allies within Egypt and overseas.

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-- Molly Hennessy-Fiske