Since Morsi's ouster, nearly 2,000 Muslim Brotherhood members have been arrested, its top leaders referred to courts over charges of inciting murder and violence, and hundreds of Morsi supporters have been killed. Morsi himself has been detained incommunicado.
On Friday, authorities arrested Ahmed Soubaei, a spokesman for the Freedom and Justice party, the Brotherhood's political arm, after raiding his house, the group said on its official website.
In a reflection of the chaos, the spokesman of the liberal al-Dustour party Khaled Dawoud came under attack when he drove past a group of pro-Morsi supporters marching on a street near Tahrir Square. The assailants dragged him from his car, beat him and stabbed him in the arm, Dawoud was quoted as telling the state-run Al-Ahram news site.
His party was founded by leading pro-democracy figure Mohamed ElBaradei, who acted as a vice president after Morsi's ouster but quit in protest to state crackdown on the Brotherhood.
ElBaradei tweeted that the attack reflects "the adversity in which we live," referring to his fears of violence between rival parties.
The Brotherhood appears to be angling to endure a crackdown that while painful also helps keep group cohesion under the pressure of a shared plight. It has publicly stuck to its most hard-line demands the reinstatement of Morsi as president and the restoration of the Morsi-era constitution.
Some Brotherhood members recognize the possibility for that has passed. But the group uses the demands to energize its members and keep up street pressure as leverage in any eventual negotiations, which could bring concessions like easing the crackdown or releasing jailed members.
In an attempt to turn Oct. 6, a national holiday seen by Egyptians as a military victory in the 1973 war with Israel, into a milestone, the group called upon its supporters to converge into Tahrir Square in a show of force.
Meanwhile, state media and anti-Islamist private networks aired national songs around the clock along with documentaries of the war glorifying the military.
Protesters encircled security forces and army troops guarding Tahrir Square from two main entrances, one near Egyptian museum and a second from the square's southern edge. That prompted riot police to fire volleys of tear gas to send the demonstrators away.
All the way to Tahrir Square, the protesters' chants against the military sparked clashes with civilians believed to be supporters of the military. Shots were fired and rocks were thrown.
An Associated Press reporter saw protesters pushed away and chased by other Egyptians armed with sticks and bottles. The two sides started hurling stones just steps from the Egyptian museum.
"We will go protest and take all streets possible," said Mohammed Said, 45, during a march from the Dokki neighborhood to Tahrir. "We will get in Tahrir at any price."
At least four people were killed in Cairo and 40 injured nationwide, Health Ministry official Khaled el-Khateb said.
Bystanders in the area had little sympathy for the protesters.
"The Muslim Brotherhood won't be able to take the square. None of the people here stands with them," said Ahmed Youssef, a 59-year-old taxi driver. "I wish the state really enforces the state of emergency and outlaws all kinds of protests. We can't live normally this way. Is this the way to democracy?"
In southern Cairo, residents holding wooden and metal sticks formed a human chain and closed a bridge leading to the district of Manial, where the pavement on the two sides of the main road was demolished and other streets were littered with stones and broken glass.
Another rally ended at a Defense Ministry building and a second at Rabaah el-Adawiya mosque in eastern Cairo, where a pro-Morsi protest camp was violently dismantled on Aug. 14. Troops backed with armored vehicles beefed up security in the vicinity of the mosque, where protesters chanted slogans against the military.
Hundreds of protesters also hurled stones at troops guarding the Defense Ministry, but most were dispersed after a 7 p.m. curfew began.
Authorities declared a state of emergency in mid-August and imposed a night curfew in Cairo and several other areas to try to quell the violence.
Across the country, similar clashes broke out, and authorities said 44 protesters were arrested in the southern province of Assiut.
Earlier in the day, at least two Egyptian soldiers were killed in an attack by suspected militants on an army convoy east of Cairo.
___
Associated Press writer Maggie Michael contributed to this report.
