(CNN) -- More than 130 people were injured in clashes that started during anti-government protests in several Egyptian cities, health ministry official Ahmed Omar told CNN.
At least 100 of the injuries Friday occurred in the province of Gharbia, said another ministry official, Mohamed Sharshar.
"Violent protesters continue to throw Molotov and fireworks at Itahadiya presidential palace gate" in Cairo, the Muslim Brotherhood's official English-language Twitter account reported.
In a statement from the prime minister's office, Hesham Qandil condemned the clashes, saying it was up to the organizers to prevent acts of violence and vandalism, and that any criminal and terrorist acts would be dealt with seriously.
Mohamed Soltan, another health ministry official, said most of the injuries were related to rock throwing and tear gas inhalation. One person in the provincial capital of Kafr el-Sheikh was wounded by birdshot pellets, he said.
One death was reported, in the Cairo neighborhood of Shubra, but it was related to low-blood sugar, he said.
Marches had been planned following afternoon prayers in provinces to mark what protesters dubbed "the Friday of Dignity."
Injuries were reported in Kafr el-Sheikh, Gharbiya, Menoufia, Sharkeya and Gharbiya, but clashes occurred in other provinces as well.
They first broke out in Tanta, the provincial capital of Gharbia. That was the hometown of 28-year-old Mohamed el-Guindy, who died last Sunday during a clash with police.
The nation has been rocked by violence since last month's second anniversary of its revolution. Protesters have fumed over the slow pace of change and recent edicts by President Mohammed Morsy, who imposed a 30-day curfew on areas engulfed by violence.
"The continued attacks suggest a real breakdown in central power, we're coming close to that," said Steven Cook, a senior fellow at the Council on Foreign Relations, last week. "None of the political forces have control over the people in the streets."
Amid the political and economic discontent, Morsy and opposition groups had vowed to keep their supporters off the streets in an effort to avoid further bloodshed.
Last week, anti-government protesters ignored Morsy's curfew in cities along the Suez Canal and clashed with police and military troops, raising more questions about the stability of the Middle East's most populous nation.
Prior to stepping down as U.S. Secretary of State, Hillary Clinton told CNN that a collapse of the Egyptian state could portend trouble for the broader region.
"I think that would lead to incredible chaos and violence on a scale that would be devastating," she said. "There has to be some understanding by the new government that the aspirations that the people were expressing during the revolution in Egypt have to be taken seriously."
The protests are the latest in the seesaw struggle between Egypt's first democratically elected president and dissidents who say his leadership is a throwback to past dictatorships, particularly the reign of President Hosni Mubarak, toppled two years ago in the popular revolt.
Dozens of deaths have resulted, prompting Navi Pillay, the U.N. high commissioner for human rights, to denounce the violence and call for dialogue among all parties.
She said Morsy's state of emergency declarations should be governed by the rule of law, in line with international standards, and urged him to listen to the demands of demonstrators and take action to deal with problems in the judicial system.
Journalist Adam Makary contributed to this report