CAIRO — Egyptian soldiers and police set fire to protest tents in Cairo’s Tahrir Square and fired tear gas and rubber bullets Sunday to drive out thousands demanding that the military rulers quickly transfer power to a civilian government. At least 11 protesters were killed and hundreds were injured.

It was the second day of clashes marking a sharp escalation of tensions on Egypt’s streets a week before the first elections since the ouster of longtime authoritarian leader Hosni Mubarak in February. The military took over the country, promising a swift transition to civilian rule. But the pro-democracy protesters who led the uprising have grown increasingly angry with the ruling generals, and suspect they are trying to cling to power even after an elected parliament is seated and a new president is voted in.

The military-backed Cabinet said in a statement that elections set to begin on Nov. 28 would take place on time and thanked the police for their “restraint,” language that is likely to enrage the protesters even more.

The two days of clashes were some of the worst since the uprising ended on Feb. 11.

They were also one of only a few violent confrontations to involve the police since the uprising. The military, which took over from Mubarak, has repeatedly pledged to hand power to an elected civilian government, but has yet to set a specific date. The protests over the past two days have demanded a specific date be set.

According to one timetable floated by the army, the handover will happen after presidential elections late next year or early in 2013. The protesters say this is too long and accuse the military of dragging its feet. They want a handover immediately after the staggered parliamentary elections, which begin on Nov. 28 and end in March.

The protesters’ suspicions about the military were fed by a proposal issued by the military-appointed Cabinet last week. It would shield the armed forces from any civilian oversight and give the generals veto power over legislation dealing with military affairs.

But other concerns are also feeding the tensions on the street. Many Egyptians are anxious about what the impending elections will bring. Specifically they worry that stalwarts of Mubarak’s ruling party could win a significant number of seats in the next parliament because the military did not ban them from running for public office as requested by activists.

The Supreme Council of the Armed Forces issued a statement expressing “regret for the events.”

The council doesn’t intend “to extend the transitional period and will not permit by any means hindering the process of democratic transition,” it said in a statement read out on state TV.

Clashes also took place in the city of Suez east of Cairo, the coastal city of el-Arish in the Sinai Peninsula, the city of Alexandria and Assiut in southern Egypt.