A civilian has been killed at a protest marking the two-year anniversary of the military coup in Egypt, a health ministry official said.
Supporters of the now-banned Muslim Brotherhood said police opened fire on protesters in Cairo's al-Maadi district on Friday, also injuring dozens.
Two years since the country's first democratically elected president, Mohamed Morsi, was overthrown, Egypt is in turmoil with government forces cracking down on Morsi's Muslim Brotherhood and heavy fighting shaking the Sinai Peninsula.
Hundreds of mostly young demonstrators held several small protests in Cairo suburbs on Friday, carrying pro-Morsi signs and chanting "down with military rule".
Meanwhile at the mosque at Cairo's iconic Tahrir Square, a prayer was held for the week's dead, including soldiers killed by armed groups in Sinai and the country's chief prosecutor, assassinated by a car bomb in the capital.
The Sinai Province group, affiliated with the Islamic State of Iraq and the Levant (ISIL), launched unprecedented simultaneous attacks on army positions on Wednesday, and clashes has since continued in the peninsula.
The army said 17 soldiers and over 100 fighters were killed on Wednesday alone, although some security sources said that scores more troops also died in the fighting.
On Friday, the state-owned MENA news agency said 70 more fighters had been killed in North Sinai by security forces over the past 48 hours.
The announcement came as the Sinai Province group claimed responsibility for firing rockets from Sinai into southern Israel. There were no casualties in the attack.
In response to the Sinai attacks and the killing of chief prosecutor Hisham Barakat, President Abdel Fattah el-Sisi wowed to clamp down on what he called terrorists and also fast-track executions of those on death row.
Action will be taken within days "to enable us to execute the law, and bring justice as soon as possible", he said. In a thinly veiled reference to jailed members of the Brotherhood, Sisi blamed the violence on those "issuing orders from behind bars", and warned: "If there is a death sentence, it will be carried out."
Since Sisi came to power, the once-ruling Muslim Brotherhood has been largely crushed. Thousands of its members and scores of leaders have been jailed and hundreds - including Morsi - handed the death penalty.
Public protests are restricted, as is political activity. Many liberal activists have also been jailed.
The same day as the wave of Sinai attacks, a special forces raid on a Cairo apartment killed 13 members of the Brotherhood. The group said they were innocents "murdered in cold blood", and called on its supporters to "rise in revolt".
Source: Al Jazeera and agencies