Bishop Michael Nazir-Ali has expressed concern over the future shape of the political landscape in the Arab world and Middle East after deadly clashes between Muslims and Christians in Egypt.

Thousands of Christians have been camped out in Cairo’s Tahrir Square to protest against sectarian violence which left 12 dead at the weekend.

Violent skirmishes spread through the rundown district of Imbaba in the western section of the city after conservative Salafi Muslims set fire to the Coptic church of Saint Mena on Saturday night. Another church nearby was also set ablaze.

The Muslims were seeking revenge in response to rumours that the church was holding a woman against her will because she wanted to convert to Islam and marry a Muslim man. The church denies the claims.

The violence has prompted fears among Christians that the unpopular regime of President Hosni Mubarak, ousted by the January 25 Revolution, will simply be replaced with an Islamic state under which conditions will be even worse for Christians.

Bishop Nazir-Ali said the violence in Cairo “shows even more clearly that there is a worrying extremist radical Islamist element to the unrest in the Arab and Islamic world at this time”.

“This will affect not only Christians but secular and moderately-minded Muslims as well – and may affect the future political shape of the Middle East,” he said.

“Since the revolution, all credible observers say the attacks on Christians have increased markedly at the hands of Wahhabi-Salafi groups.

“Their agenda is an Islamic state built on their extreme beliefs. The West is also vulnerable to this kind of extremism.”

Christian Solidarity Worldwide said its sources in Egypt fear that the government may put pressure on Copts to accept an out-of-court settlement, effectively circumventing justice and allowing the perpetrators to go unpunished.

CSW’s Advocacy Director Andrew Johnston welcomed the government’s swift response to the violence in arresting the perpetrators, but said there must be accountability for the events of Saturday.

He said reports that the army stood by for several hours while churches were burned and people killed were “particularly worrying”.

“If true, there must be accountability for such a serious dereliction of duty,” he said.

“Moreover, it is vital that the entire episode is dealt with through due process of law and not through a largely discredited reconciliation process that appears to legitimise a denial of justice to the Coptic community and to engender an atmosphere of impunity.

“The government must also make good on its promise to ensure better protection for Copts in the future, which has been articulated on a number of previous similar occasions, but has clearly been inadequately implemented.”

The US State Department today condemned the violence and “destructive attacks on churches”, and called for calm and restraint.

Egypt’s government has taken a tough stance towards instigators of the violence, with some 190 people arrested during the unrest to stand trial in the military court.

Justice Minister Abdel Aziz al-Gindi told journalists that the authorities would “strike with an iron hand all those who seek to tamper with the nation’s security”.