CAIRO (AP) -- Thousands of anti-government protesters, some hurling rocks and climbing atop an armored police truck, clashed with riot police Tuesday in the center of Cairo in a Tunisia-inspired demonstration to demand the end of Hosni Mubarak's nearly 30 years in power. (Scroll down for live updates.)

Police responded with blasts from water cannons and set upon crowds with batons and acrid clouds of tear gas to clear demonstrators crying out "Down with Mubarak" and demanding an end to Egypt's grinding poverty, corruption, unemployment and police abuses.

Tuesday's demonstration, the largest Egypt has seen for years, began peacefully, with police showing unusual restraint in what appeared to be a calculated strategy by the government to avoid further sullying the image of a security apparatus widely seen as little more than corrupt thugs in uniforms.

With discontent growing over economic woes, and the toppling of Tunisia's president still resonating in the region, Egypt's government - which normally responds with swift retribution to any dissent - needed to tread carefully.

But as crowds filled downtown Cairo's Tahrir Square - waving Egyptian and Tunisian flags and adopting the same protest chants that rang out in the streets of Tunis - security personnel changed tactics and the protest turned violent. ___

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