"We are facing the anti-revolutionary groups who are convinced that any success of the revolution was an even greater threat to their interests and so are trying to fuel confessional conflict," wrote flagship state daily Al-Ahram.
Fierce clashes broke out between Christians and Muslims in northwest Cairo's working-class
district of Imbaba where 12 people were killed, scores injured and a church set ablaze.
Among the dead were six Muslims and four Christians while two bodies were still unidentified.
The two groups clashed after Muslims attacked the Coptic church of Saint Mena in Imbaba in a bid to free a
Christian woman they alleged was being held against her will because she wanted to convert to Islam.
Since the ouster of former president Hosni Mubarak,
Egypt has been gripped by insecurity and sectarian unrest,
amid -- by the government's
admission -- a "counter-revolution" by remnants of the old regime aimed at sowing chaos.
Ali Gomaa, Egypt's grand mufti and chief interpreter of Islamic law, was quoted in main independent daily Al-Masri Al-Yom as warning of the potential for
civil war, "because of outlaws who want to defy the authority of the state."
The Interior Minister Mansur al-Issawi, meanwhile, denied rumours that weapons had been stored in Saint Mena church.
"Contrary to rumours that there were weapons inside the church, it was the owner of a
cafe near the church who fired a gun," he was quoted as saying in another government daily, Al-Akhbar.
The Salafis, a puritanical Islamist sect accused of being behind the Imbaba clashes, denied they had any role in the violence.
Prominent Salafi cleric in Cairo, Abdel Moneim al-Shahat, said the Imbaba clash "does not reflect the Salafist thought which prohibits the incitement of confessional conflict."
Saturday's violence also angered ElBaradei, a prominent figure in the 18-day uprising that toppled Mubarak, who called on Twitter for swift action against such "religious extremism and practices of the Middle Ages."
Egypt's government warned on Sunday it will use an "iron hand" to ensure national security after the clashes.
Authorities would "strike with an iron hand all those who seek to tamper with the nation's security," Justice Minister Abdel Aziz al-Gindi told reporters after the
cabinet held crisis talks on the violence.
Egypt's
military rulers said 190 people detained in connection with the clashes would face military trial.
The Supreme Council of the Armed Forces, in power since the
popular uprising toppled Mubarak, said the move was a "deterrent" to all those who sought to sow strife in the country.
Those arrested after the Saturday violence must be brought before military courts, while a curfew was imposed until Monday at 0900 GMT in the area, where
soldiers and riot police were deployed in force.
For months, Egypt is experiencing a rise in sectarian tensions amid claims that
Christian women who converted to Islam were kidnapped and held in churches or monasteries.
Egyptian Copts, who account for up to 10 percent of the country's 80-million people overwhelmingly made up of Sunnis, complain of discrimination and have been the
targets of fairly regular sectarian attacks.
