The Egyptian government has warned it will use "an iron fist" to ensure national security after clashes between Muslims and Christians in Cairo.
After an emergency cabinet meeting, Justice Minister Abdel Aziz al-Gindi said the government would use anti-terror laws to combat those threatening national security.
The army said more than 190 people detained after the fatal clashes will face military trials.
The Supreme Council of the Armed Forces, in power since a popular uprising toppled president Hosni Mubarak in February, called the move a "deterrent" to all those who sought to instigate strife.
Saturday's clashes in Imbaba suburb of north-western Cairo left 12 people dead and 232 injured, state television said.
The violence began after several hundred Salafist Muslims had gathered outside the Coptic Saint Mena church.
They were reportedly protesting over allegations that a Christian woman was being held there against her will because she had married a Muslim man and wanted to convert to Islam.
Rival groups threw firebombs and stones, and gunfire was heard, the BBC reports.
The church and one other, as well as some nearby homes, were set alight, and it took some hours for the emergency services and the military to bring the situation under control.
