Thousands of protesters swarmed Cairo's Tahrir Square on Tuesday to demand an end to military rule, heightening tension after days of deadly clashes that threaten to derail next week's legislative polls.

The ruling Supreme Council of the Armed Forces (SCAF) began crisis talks with a number of political forces in a bid to defuse the crisis, state media reported.

Egypt's military rulers have failed to live up to their promises and have even committed worse rights abuses than the regime of ousted autocrat Hosni Mubarak, Amnesty International said on Tuesday.

The London-based watchdog made the criticism in a report that comes after Egyptian police and troops killed at least 24 people in three days at protests against military rule in Cairo's Tahrir Square and across the country.

Egypt's ruling Supreme Council of the Armed Forces on Monday rejected the resignation of Prime Minister Essam Sharaf's cabinet, state television reported, quoting a military source.

Cabinet spokesman Mohammed Hegazy said earlier that the cabinet had resigned, as deadly clashes raged for a third day in Cairo's Tahrir Square.

Egypt's stock exchange tumbled 4.04 percent on closing on Monday, as deadly clashes between police and protesters threatened to overshadow the first parliamentary polls since Hosni Mubarak was toppled.

The main EGX-30 index dipped to 3,860.99 points -- a drop of 4.04 percent -- as clashes raged into a third day in Cairo's Tahrir Square between security forces and protesters demanding the end of military rule.

France on Monday condemned the killing of pro-democracy protesters in Egypt and called for elections to be held as planned next week in order for the country's democratic transition to succeed.

"France is deeply concerned by the clashes in recent days. It condemns the violence that led to the deaths of over 20 demonstrators," foreign ministry spokesman Bernard Valero told journalists.

Egypt's culture minister has resigned in protest at the government response to demonstrations in Cairo's Tahrir Square in which more than 20 people have died, the official MENA agency said on Monday.

Emad Abu Ghazi handed his resignation to the ruling Supreme Council of the Armed Forces -- which took power when Hosni Mubarak was ousted in February -- "in protest at the government's handling of the recent events in Tahrir Square," MENA said.

One police officer was killed and another injured in Egypt's Sinai on Monday during clashes with members of an Islamist group suspected of attacks on a pipeline, a security official said.

Police officers in the north Sinai town of el-Arish were preparing to arrest individuals suspected of belonging to the Islamist al-Takfeer wal Hijra, when they were shot at and clashes ensued killing one officer and wounding another, the official said.

At least four people were killed on Sunday as security forces tried to clear protesters from Cairo's Tahrir Square, casting a dark shadow over Egypt's first elections since Hosni Mubarak's downfall.

Police and military forces used batons, tear gas and birdshot to clear the central square of thousands of protesters who are demanding that the ruling military cede power to a civilian authority.

Syrian anti-regime protesters and their Egyptian supporters clashed with backers of President Bashar al-Assad on Sunday outside the Arab League headquarters in Cairo.

The anti-Assad protesters, who had set up camp outside the Arab League, said about 150 Assad loyalists carrying a poster of the embattled president tried to attack their tent but they drove them off with the help of Egyptian protesters.

Two people were killed and hundreds injured in Egypt this weekend as police fired rubber bullets and tear gas at protesters in a violent countdown to the first elections since the ouster of Hosni Mubarak.

"Down with Tantawi," hundreds of demonstrators cried in Cairo's iconic Tahrir Square, referring to the post-Mubarak military ruler Field Marshal Hussein Tantawi, as they lobbed rocks and other objects towards armed police.