Egyptians have begun casting their ballots in the first parliamentary elections since a popular uprising ended the 30-year rule of former president Hosni Mubarak in February.

Voters stood in long lines early Monday, well before polling stations opened. Thousands of Egyptian judges are monitoring the process.

The staggered polls to elect parliament's lower house began in the main cities of Cairo and Alexandria, as well as Luxor, Port Said and five other provinces. A runoff for those areas is scheduled for December 5.

Egypt's 27 provinces are voting in three separate rounds in a process that concludes in early January. Elections for the upper house will then take place, ending in March, after which the assembly will write a new constitution.

The influential Muslim Brotherhood, an Islamist movement officially banned since the 1950s, is poised to win a stronger role in a country effectively run by the military for nearly six decades as an authoritarian secular state.

But Egypt's ruling generals have established a convoluted electoral system that many fear will result in a legislature lacking credibility. Army generals have made clear the new assembly would have no right to remove a government appointed by the ruling military council.

The head of that body, Field Marshal Hussein Tantawi, defended the army's privileged status in Egyptian society, declaring Sunday that “the position of the armed forces will remain as it is,” even after a new constitution is passed.

Tantawi said the country is at a crossroads and can choose either successful elections “leading Egypt towards safety” or face dangerous hurdles that the armed forces “will not allow.” He also warned of “extremely grave” consequences if the country's current political turmoil does not end quickly.

Nine days of widespread clashes, with 42 people killed and more than 3,000 injured, have heightened fears of violence among supporters of rival candidates.

The general's warning came as thousands of demonstrators filled Cairo's Tahrir Square Sunday for another massive protest demanding Egypt's military immediately cede power to a “national salvation government” that would run the country until a president is elected.

A number of the revolutionary youth groups leading the demonstrations have proposed that opposition leader Mohamed ElBaradei head an interim civilian administration with deputies from across the political spectrum. The proposed body would replace the military council in supervising Egypt's transition to democracy.

ElBaradei says he would abandon his bid for Egypt's presidency if formally asked to lead such a government.

Meanwhile, saboteurs attacked a gas pipeline in Egypt's Sinai Peninsula early Monday, just hours before polls opened. The assault marks the ninth time this year attackers have targeted the pipeline, which supplies natural gas to Israel and Jordan. The last incident took place Friday.

Earlier this month, Egyptian police arrested a leading member of an armed Islamist group , suspected of several of the bombings. Previous attacks have disrupted fuel supplies for weeks.