Updated

Egyptians emerged Thursday from an all-night curfew imposed after the country's worst violence in decades, with 370 people killed as security forces broke up protests in support of ousted president Mohamed Morsi.

Light traffic returned to the streets after a tense night, following the army-backed interim government's decision to impose a month-long, nationwide state of emergency and curfews in 14 provinces.

The health ministry continued to update its toll, saying at least 327 civilians were killed throughout the country on Wednesday.

That was in addition to 43 police killed in the violence, according to the interior ministry, and put the day's total toll at 370.

Despite the violence, Egypt's press trumpeted the end of the pro-Morsi demonstrations, which had occupied two Cairo squares since the Islamist president's July 3 ouster by the military.

"The nightmare of the Brotherhood is gone," the daily Al-Akhbar's front page headline read.

"The Brotherhood's last battle," added Al-Shorouk.

The newspapers carried photos of protesters brandishing weapons and throwing stones, but none from makeshift morgues where dead protesters were lined up in rooms slick with blood.

At least four churches were attacked as police broke up the protests, with Christian activists accusing Morsi loyalists of waging "a war of retaliation against Copts in Egypt".

The day's violence was Egypt's worst in decades, exceeding even that seen during the 18-day uprising that ousted president Hosni Mubarak.

The Brotherhood remained defiant on Thursday, with spokesman Gehad al-Haddad saying demonstrations would continue.

"We will always be non-violent and peaceful. We remain strong, defiant and resolved," he tweeted.

"We will push forward until we bring down this military coup."

Morsi loyalists have insisted that their demonstrations are exclusively peaceful, but an AFP reporter saw several protesters carrying weapons at Rabaa on Wednesday.

The violence prompted vice president and Nobel laureate Mohamed ElBaradei to resign, saying he was troubled over the loss of life, "particularly as I believe it could have been avoided".

"It has become too difficult to continue bearing responsibility for decisions I do not agree with and whose consequences I fear," he said.

The dramatic assault on the sit-ins began shortly after dawn on Wednesday, with security forces firing tear gas before storming the sites.

The operation surprised many, coming after officials described plans to gradually disperse the protests over several days in a bid to avoid violence.

Some Morsi supporters were eventually able to leave the Rabaa site through a safe passage, flashing victory signs as they left.

By Wednesday evening, a security official said Rabaa al-Adawiya was "totally under control", adding: "There are no more clashes".

In the smaller of the protest camps, at Al-Nahda square in central Cairo, police said they had control of the area after just two hours.

Dozens rounded up in the dispersal were shown sitting on the ground, handcuffed and surrounded by security forces.

Europe's leading powers, along with Iran, Qatar and Turkey, strongly denounced the use of force by the interim government.

Turkish Prime Minister Recep Tayyip Erdogan Thursday called for an urgent UN Security Council meeting over the crackdown, while Denmark announced it has suspended development aid to Egypt.

The White House said Washington, which provides Egypt with $1.3 billion in annual military aid, "strongly condemns" the violence against the protesters and opposed the imposition of a state of emergency.

But Egypt's interim prime minister Hazem al-Beblawi praised the police for their "self-restraint" and said the government remained committed to an army-drafted roadmap calling for elections in 2014.

Interior Minister Mohamed Ibrahim said no more protests would be tolerated, and in several neighbourhoods residents clashed with angry Morsi loyalists.

The violence was not confined to Cairo, with clashes between security forces and Morsi loyalist breaking out in the northern provinces of Alexandria and Beheira, the canal provinces of Suez and Ismailiya, and the central provinces of Assiut and Menya.

In Alexandria, hundreds of angry Morsi supporters marched Wednesday through the streets armed with wooden clubs chanting "Morsi is my president."

The violence was a dramatic turn of events for the Muslim Brotherhood, who just over a year ago celebrated Morsi's victory as Egypt's first elected president.

His turbulent year in power, marred by political turmoil, deadly clashes and a crippling economic crisis, turned many against the Islamist movement, with millions taking to the streets on June 30 to call for his removal.