Egypt's second biggest Islamist party, Nour, on Friday rejected proposed changes to the constitution that would outlaw parties founded on religious grounds, and called the move a "sword drawn" against Islamists.
The proposal, made during meetings of the constitutional committee this week but not yet formally approved, came days after a Cairo court separately banned the Muslim Brotherhood, Egypt's dominant Islamist force.
"It's wrong to blame the whole Islamist current for the mistakes of the Muslim Brotherhood," said Nour Party head Younes Makhyoun in a statement. "We reject this article completely because it is discriminatory and exclusionary.
"By what right does this article aim a drawn sword at some parties? Are we going to put an article in the constitution that bans founding parties on liberal, secular, socialist or Nasserist grounds?"
Islamist political parties formed after the downfall of veteran autocrat Hosni Mubarak in 2011 dominated elections, and the Brotherhood's Mohamed Morsi became Egypt's first freely elected president.
But after a year in power, huge demonstrations against his rule prompted the army to oust him. Security forces have launched a crackdown on the Brotherhood in which hundreds of Islamists were shot dead on the streets of Cairo and thousands more, including Morsi, arrested.
Any move to ban religious parties would redraw Egypt's political map and turn the clock back to the days under Mubarak when Islamists were not allowed to form political parties.
Nour walks out
Nour, founded shortly after the popular uprising against Mubarak, backed Morsi's overthrow in July by signing up to a road map for Egypt's political transition that included amending the constitution and setting a time frame for new elections.
But earlier this month, Nour, whose representative is one of only two Islamists on the 50-member constitutional committee, walked out of a meeting to protest against moves to curb the influence of Islam in state affairs.
Moves to outlaw Islamist movements and parties have raised fears in Egypt that supporters who see little hope for a democratic future may resort to violence.
Militant groups have long been active in the Sinai Peninsula bordering Israel and the Palestinian Gaza Strip, a region where central authority is weak and attacks on security forces have spiked since Morsi's ouster.
More than 100 members of the security forces have been killed in Sinai since the overthrow, and on Friday a policeman was shot dead by gunmen in the city of El-Arish in the north of the region, state television reported.
In a separate incident in Sinai, an armored personnel carrier was hit by an improvised bomb on a road near Sheikh Zuweid which injured one soldier and triggered shooting in which one man died, according to state news agency MENA.
MENA also said two explosive devices detonated near police check points on the outskirts of Cairo, wounding two policemen.
And in Alexandria, several hundred pro-Morsi protesters took to the streets and clashed with residents, leaving at least five injured with birdshot and gunshot wounds, medical sources said.