CAIRO, Egypt – Two Egyptian fighter planes blasted across the smog-filled skies of Cairo, just minutes after the military-imposed curfew began, leaving thunderous booms in their wake that few in the capital could miss.

The low, circular patterns these planes traced over Cairo’s city center, Tahrir Square, produced a resounding show of force that seemed aimed at the thousands of anti-government demonstrators chanting below.

But hours after the 4 p.m. curfew started on Sunday afternoon, defiant Egyptians remained in the square, continuing their calls for an end to the regime led by 82-year-old President Hosni Mubarak.

“We will never leave! But he will leave!” sang one young protester who carried a sign that read “Game Over Mubarak,” written in both Arabic and English.

Opposition leader Mohamed ElBaradei, emboldened after the Muslim Brotherhood, Egypt’s largest Islamic group, threw its support behind the secular leader, joined protesters on Sunday in the square to call on Mubarak to step down. On Monday morning, ElBaradei called for a million people to flood the streets on Tuesday in another push to bring down Mubarak.

Meanwhile, foreign governments from Turkey to Germany to the United States organized evacuation flights for their citizens trapped inside Cairo, Egypt's smoldering capital.

But after six days of unprecedented civil unrest that has spread throughout the country, Mubarak appears to be digging in, slowly reasserting its authority.

The curfew, which had largely been ignored for days, has begun to be enforced more seriously and Mubarak has been reassembling a government, appointing several new ministers after sacking his cabinet on Saturday. And the country’s police force – a major target of resentment and anger during the protests – is preparing to redeploy after a brief recall while the military rolled into Cairo.

In spite of these recent moves, and sometimes because of them, Egyptians said they were undeterred in their quest to change the leadership of a government that has ruled them with little challenge for nearly three decades.

“We are so happy to be here. All Egyptians have risen to the occasion,” Alia Essam, 27, one of the many female protesters in the square. “I hope – like many here hope – that these will be Mubarak’s last days in office.”

Tahrir, or Liberation, Square, which until recently was a massive transit hub known for its gridlock and unheeded traffic lights, has now become a pedestrian area where thousands of Egyptians rally daily to demand freedom, democracy, and more opportunity in a stagnating economy.

Much of the blame in the square was aimed directly at Mubarak, and his political moves did little to mollify protesting Egyptians eager to see fresh faces.

Many there voiced their dissatisfaction with Mubarak’s promotion on Saturday of Egypt’s spy chief, Omar Suleiman, to vice president. It was an extraordinary move. Since taking office in 1981, Mubarak had never publically declared a possible successor to his presidency.

Despite the widespread frustration, the huge crowds in Tahrir Square have remained largely peaceful in their calls for regime change.

Just a few blocks away, however, violence between protesters and police holdouts raised concern that there could be more turbulence when security forces return to work this week.

Hundreds of protesters clashed with Egyptian police forces outside their stronghold, the interior ministry, on Saturday. An area within a four-block radius of the ministry resembled a war zone, with police gunfire echoing as the two sides battled back and forth for control of the narrow streets leading to the building.

Protesters, armed with rocks, bottles, and Molotov cocktails, made several attempts to capture the ministry, which they said symbolized a police force known for its corruption and impunity.

“Every time I go to a police station to register a document, I have to pay them bribes to process my paper work,” said a 37-year-old English teacher who identified himself only as Wael.

The police, however, made the first move on Saturday morning, swiftly and with aggression.

Around 30 officers, sprinting, fanned out across several blocks around the ministry in an attempt to rebuild barricades on ground they had retreated from in clashes a day earlier. Police fired shotgun rounds into the air to announce their presence.

Swelling numbers of Egyptians, however, eventually overran their lines and torched several empty police vehicles along the road. The group, many of whom were no older than 17, fashioned scrap metal into makeshift shields and set up a defensive position behind apartment buildings and the charred black skeletons of vehicles.

Shady Saad, 24, was among those tossing rocks at the police, angry after sustaining 10 separate hits from rubber bullets the night before, he said.

Police forces fell back to their fortress-like garrison, firing volleys of rubber bullets in the direction of anyone attempting to advance upon them.

“Come on! Let’s go!” screamed one young man, rallying dozens to push forward while police reloaded.

But by nightfall, it was mostly over. Dozens of injured protesters slumped along buildings, several gushing blood from their faces and throats.

Five people reportedly died during the fighting, according to eyewitnesses.

With police fortifying the perimeter around the ministry, some of the young protesters vented their frustration by vandalizing storefronts in the area.

By the time the dust had settled, the streets where the battle took place were strewn with shotgun casings, shattered glass and burned paper. Several nearby fast-food chains, including a McDonalds, were completely ransacked.

The widespread riots and looting left many Cairenes eager for a return to order on the streets and many began to take control of their own neighborhoods, setting up road blocks and patrols by residents armed with sticks, clubs, knifes and even guns.

The sound of gunfire at night has been common throughout the capital over the past several days.

Cherif Barakat, who witnessed the violent clashes near the interior ministry, hid in his downtown apartment most of the weekend, scared to leave with a mob of looters roaming the streets. But echoing many other resident of Cairo, Barakat pointed out the obvious challenges Egypt’s security forces will face when they redeploy.

“I’ve been trembling with fear because of everything happening on this street,” said Barakat, referring to the fighting. “I think we’re all disgusted by the amount of looting going on now. Then again, how safe is it for us if the police are opening fire on our streets?”

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