CAIRO — Fresh concrete blocks, knots of barbed wire and lines of heavily-armed riot police have once more interrupted the flow of downtown Cairo's bustling colonial-era streets, following bloody clashes earlier this month between police and protesters near the capital’s interior ministry.

The increasing number of walls, built by law enforcement troops under fire, are the last lines of defense against the activist-led, rock-and-Molotov battles for Egypt’s interior ministry, which controls the country's powerful police force. It's an institution many here say was crafted as ousted President Hosni Mubarak’s own personal army.

In the wake of Egypt’s deadly football clashes in Port Said last month, in which hundreds of riot police are accused of having simply stood by while football fans were brutally murdered by fellow spectators, the question of who will control Mubarak’s hated but indispensable police force is again at the forefront.

“It is the most important goal of the revolution,” said Adel Abdel Menem Ahmed, a leading member of the Muslim Brotherhood’s Freedom and Justice Party (FJP) in Beni Suef province, of restructuring and purging the country’s interior ministry of Mubarak-era cronies. FJP secured a near-majority in recent parliament elections.

“You cannot live in a house with thieves and expect to be safe,” he said.

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But little if any progress has been made by way of reforming the police — who are underpaid, corrupt and trained almost solely to crush the political opposition — since Egyptians torched hundreds of their stations in the popular uprising last year that led to Mubarak’s fall.

And while much of the debate over Egypt’s new power players is focused largely on the military council and the newfound clout of the Islamists, it may be those who end up at the helm of the vast security apparatus nurtured under Mubarak, but which largely withdrew from the streets following his ouster, who become the ultimate powerbrokers of post-revolution Egypt.

Egypt’s police force traces its modern history to a 17th century Ottoman military corps that fostered political coups and served as kingmakers and breakers, observers here say.

In Egypt, the corps “were intended to maintain public order,” said Pascale Ghazaleh, an assistant professor of history at the American University in Cairo.

But similar to the modus operandi of Egypt’s current force, “members tended to create alliances with local groups and to serve as a sort of urban militia that participated in several uprisings,” she said.

Many here worry that the ministry and its myriad agencies — which to this day employ extensive networks of informants and known criminals, and run profitable protection rackets — are still under the thumb of Mubarak associates.

Pro-democracy activists say they would like to see sweeping police reform that would remake security forces as protectors of the public rather than defenders of a Pharaoh-like leader.

“To a large extent, the interior ministry is still controlled by those from the old regime,” said Ahmed Al Nahhas, a prominent Brotherhood member in the seaside Alexandria governorate. “This is a huge problem because it means citizens and activists are still under threat.”

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As new allegiances are cast and old ones crumble and shift in the complex post-revolt landscape, the mammoth police force is up for grabs. A diverse and often competing group of political actors all vie for influence in the new Egypt.

The struggle for command of the interior ministry will take place both behind-the-scenes and on the streets, analysts and activists here say. And it will not be pretty.

“The scary thing is, we are currently in the purge phase of the revolution,” said Hisham Al Kassem, a long-time anti-Mubarak activist and founder of Egypt’s first independent daily newspaper, Al Masry Al Youm.

“The former regime members are beginning to realize that the nightmare of the revolution is not going away,” he said. “They are afraid, and they have enormous funds they could use to try to derail the process in any way.”

It is widely believed that right now the army, through the ruling Supreme Council of Armed Forces (SCAF) — a cluster of generals that seized power during the uprising — is ultimately in control of the interior ministry and its foot soldiers.

But the military’s lack of transparency as Egypt’s caretaker government means little is known about who is actually calling the shots.

“Theoretically they [the army] have the final say in everything going on in the ministry of the interior,” Al Kassem said. “But they are barely propping it up, and it will likely take years to control.”

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But as the Muslim Brotherhood, persecuted for decades by the police, seek to leverage power from their new position in parliament — calling for a radical overhaul of internal security forces and a civilian minister of interior — the army’s historical suspicion of the Islamists is also likely to resurface, observers here say.

Ever since former Egyptian president and army officer, Gamal Abdel Nassar, violently suppressed the movement following an attempt on his life by an Islamist militant in 1954, the Brotherhood’s activism has irked Egypt’s military.

“[The] suspicion is rooted in relations between the army and the Brotherhood since 1954 and Nasser’s crackdown on the Brotherhood,” Ghazaleh said. “Possibly relations deteriorated even further after [Egyptian President Anwar] Sadat’s assassination” by an Islamist.

Brotherhood leaders told GlobalPost they seek to eliminate all military influence from any future police force.

But, Ghazaleh said, “The army would be very leery of anything controlled by the Brotherhood.”

For their part, civil society groups, which are often at odds with SCAF and which say they have only a limited audience with the new FJP lawmakers, banded together to form the “National Initiative to Rebuild the Police Force.”

The initiative calls for swift demilitarization and civilian control of the police, but also a boost in law enforcement wages and expansion of officers’ occupational rights and civic training, which they see at the root of much of the corrupt police practices here.

“I can’t please everyone,” Gen. Abd Al Aziz Al Nahhas, the chief of police in the southern governorate of Sohag, said in a rare, candid admission from a police official.

“We need better technological resources and better pay. There needs to be a general overhaul of government institutions in general not just the police force," he said. “We are just waiting for an elected government.”