By Dominic Waghorn, Sky News Correspondent, in Cairo
At least 36 people in Egypt have died and over 1,000 were hurt in fierce clashes between supporters and opponents of deposed president Mohamed Morsi.
Supporters of the former leader marched to the Cairo barracks of the Republican Guard chanting "down with military rule" after a Muslim Brotherhood rally at the city's Rabea al Adaweya mosque.
Shots were fired as protesters hung pictures of Mr Morsi on a barbed wire barrier around the military complex. At least three demonstrators were shot by the military.
Downtown Cairo witnessed the same street battles played out two-and-a-half years ago, this time with Morsi supporters fighting their enemies with rocks, clubs and fireworks. One person was killed in their clashes.
Following the violence, the country's interim president Adli Mansour held talks with General Abdel-Fattah el-Sissi - the army chief who is also defence minister - and interior minister Mohammed Ibrahim who is in charge of the police.
It was the first time Mr Mansour has worked from the president's main offices since he was sworn-in on Thursday, after the military overthrew Mr Morsi - the country's first democratically elected president.
An anti-Morsi protester with evidence of gun cartridges A pro-Morsi crowd crossed the Sixth Of October bridge heading towards Tahrir Square, provoking a fierce confrontation.
The Egyptian army said troops were responding only with blank rounds and tear gas.
However, anti-Morsi youths showed Sky News what their enemies had done to them, brandishing used shotgun cartridges and pellet wounds.
"They are terrorists and we should get rid of them," they said. "They're using automatic weapons and shotguns."
Egyptian elite soldiers guard a military building in Cairo The atmosphere was febrile. Changing in a second. Turning from triumphant to panicked, as the crowd scattered thinking their attackers had returned.
"The Muslim Brotherhood is coming here beating us shooting us," said one man. "We're here, we're alone and we need someone to help us."
As if to answer him, military armoured personnel carriers appeared from the gloom.
But this isn't a conflict against foreign invaders, it's between Egyptians.
The anti-Morsi crowd screamed curses against the ousted president venting their fury, and relief then turned against us, the Sky News crew, mistaking us for Americans.
A hurried explanation gave us time to escape.
More than 200 people have been wounded nationwide, according to officials There are now two armies of protesters on the streets of Cairo - enraged and out for vengeance, determined to prevail.
Violence also erupted in cities of southern Egypt, along the Suez Canal and in the Nile Delta, with officials reporting more than 200 people injured. Four were killed in the northern Sinai city of el Arish, where Islamists stormed a government building.
Egypt's ambulance authority said 36 people had died nationwide, including 12 people in clashes in Alexandria. Most of the fatalities were from gunshot wounds.
It came after the Muslim Brotherhood and its allies called for protesters to take to the streets on the Muslim day of prayer for what it described as a "Friday of Rage".
The leader of the Brotherhood called for followers to remain peaceful but he vowed to restore power to Mr Morsi, who was ousted in a military coup earlier this week, a year after being elected to office.
Meanwhile, lawyers for ex-president Hosni Mubarak entered a not guilty plea as his retrial for alleged complicity in the killings of protesters in 2011 resumed.
The 85-year-old former leader appeared in the dock behind bars, wearing dark sunglasses and a white prison uniform.
During the televised hearing, Cairo's criminal court heard submissions by the defence before proceedings were adjourned until August 17.
Nearly a third said they had thought about or attempted to end their life
Mr Rodney's family and legal team spoke out after the report was published
Sir Bernard Hogan-Howe said the Met "deeply regrets" the killing 
The ousted president is in custody
Anti-Morsi protesters react to the army statement
General Abdul Fatah Khalil al Sisi announces the overthrow of Mohamed Morsi
Muslim Brotherhood members and pro-Morsi supporters react in Cairo
A military helicopter above Tahrir Square
A soldier cheers with anti-Morsi protesters
Firefighters and jail workers tried to resuscitate Williams
Tens of thousands of Egyptians have staged protests across the country
Thousands joined a protest in Tahrir Square in Cairo
Mr Morsi said he would protect democratic "legitimacy" with his life
A protester sits in front of anti-Morsi artwork on a Cairo building
Theresa May signing the treaty with Jordan earlier this year
Michael Adebolajo is one of the men charged with Drummer Rigby's murder
Strong winds and low humidity allowed the blaze to spread quickly
Hundreds of homes have been destroyed by the fire
Barack Obama visiting a prison cell as senator in 2006
Nelson Mandela visiting his old prison cell in 1995