CAIRO -- Egyptian police fired tear gas at protesters demonstrating against President Mohamed Morsi's drive to hold a snap referendum on a new constitution and some broke through police lines around his palace, live television footage showed.

Several thousand protesters had gathered nearby in what they dubbed "last warning" protests against Morsi, who has angered opponents with a November 22 decree that expanded his powers.

"The people want the downfall of the regime," chanted the protesters.

Morsi ignited a storm of unrest in his bid to prevent a judiciary still packed with appointees of ousted predecessor Hosni Mubarak from derailing a troubled political transition.

Riot police had earlier mustered around the palace as activists chanted "leave, leave" and held up Egyptian flags with "no to the constitution" written on them. Other protesters assembled in front of two mosques north of Cairo before marching towards the palace.

"Many of our national leaders and youth will join us in our marches today," said Hussein Abdel Ghany, a spokesman for the opposition coalition. "Our marches are against tyranny and the void constitutional decree and we won't retract our position until our demands are met."

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Still, by early evening there was only a limited response to opposition calls for a mass campaign of civil disobedience in the Arab world's most populous country and cultural hub, where many people yearn for a return to stability.

A few hundred protesters gathered earlier near Mursi's house in a suburb east of Cairo, chanting slogans against his decree and against the Muslim Brotherhood, from which the president emerged to win a free election in June. Police closed the road to stop them from coming any closer, a securityofficial said.

Liberals, leftists, Christians and others have accused Mursi of staging a dictatorial power grab to steamroll through a constitution drafted by an assembly packed with Islamists, with a referendum planned for Dec. 15.

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Egypt's most widely read independent newspapers did not publish on Tuesday in protest at Mursi's "dictatorship". Banks planned to close three hours early, one bank official said.