Protests calling for Mubarak's ouster have been spreading since Tuesday outside of Cairo's Tahrir Square, where demonstrators have been concentrated for the past two weeks. On Wednesday, protesters also gathered at parliament, the Cabinet and the Health Ministry buildings, all a few blocks from the square, and blocked Prime Minister Ahmed Shafiq from his office.
Strikes erupted in a breadth of sectors - among railway and bus workers, state electricity staff and service technicians at the Suez Canal, in factories manufacturing textiles, steel and beverages and at least one hospital.
In one of the flashpoints of unrest Wednesday, some 8,000 protesters, mainly farmers, set barricades of flaming palm trees in the southern province of Assiut. They blocked the main highway and railway to Cairo to complain of bread shortages. They then drove off the governor by pelting his van with stones.
Hundreds of slum dwellers in the Suez Canal city of Port Said set fire to part of the governor's headquarters in anger over lack of housing.
Workers "were motivated to strike when they heard about how many billions the Mubarak family was worth," said Kamal Abbas, a labor leader. "They said: 'How much longer should we be silent?'"
Egyptians have been infuriated by newspaper reports that the Mubarak family has amassed billions, and perhaps tens of billions of dollars in wealth while, according to the World Bank, about 40 percent of the country's 80 million people live below or near the poverty line of $2 a day. The family's true net worth is not known.
"O Mubarak, tell us where you get 70 billion dollars," dozens of protesters chanted in front of the Health Ministry.
For the first time, protesters were forcefully urging labor strikes despite a warning by Vice President Omar Suleiman that calls for civil disobedience are "very dangerous for society and we can't put up with this at all."
His warnings of a possible "coup" Tuesday were taken by protesters as a veiled threat to impose martial law - which would be a dramatic escalation in the standoff. But instead of backing off, they promised more huge protests on Friday.
"He is threatening to impose martial law, which means everybody in the square will be smashed," said Abdul-Rahman Samir, a spokesman for a coalition of the five main youth groups behind protests in Tahrir Square. "But what would he do with the rest of the 70 million Egyptians who will follow us afterward."
Suleiman is creating "a disastrous scenario," Samir said. "We are striking and we will protest and we will not negotiate until Mubarak steps down. Whoever wants to threaten us, then let them do so," he added.
The protesters filling streets of Cairo and other cities since Jan. 25 have already posed the greatest challenge to the president's authoritarian rule since he came to power 30 years ago. They have wrought promises of sweeping concessions and reforms, a new Cabinet and a purge of the ruling party leadership, but Mubarak refuses their demands that he step down before September elections.
U.S.-based Human Rights Watch has said about 300 people have been killed since the protests began, but it is still compiling a final toll.
The strikes broke out across Egypt as many companies reopened for the first time since night curfews were imposed almost two weeks ago. Not all the strikers were responding directly to the protesters' calls, but the movement's success and its denunciations of the increasing poverty under Mubarak's rule resonated and reignited labor discontent that has broken out frequently in recent years.
The farmers in Assiut voiced their support for the Tahrir movement, witnesses said, as did the Port Said protesters, who set up a tent camp in the city's main Martyrs Square similar to the Cairo camp.
In Cairo, hundreds of state electricity workers stood in front of the South Cairo Electricity company, demanding the ouster of its director. Public transport workers at five of the city's roughly 17 garages also called strikes, demanding Mubarak's overthrow, and vowed that buses would be halted Thursday. It was not clear if they represented the entire bus system for this city of 18 million.
Dozens of state museum workers demanding higher wages staged a protest in front of the Supreme Council of Antiquities, crowding around antiquities chief Zahi Hawass when he came to talk to them.
Several hundred workers also demonstrated at a silk factory and a fuel coke plant in Cairo's industrial suburb of Helwan, demanding better pay and work conditions.
In the desert oasis town of Kharga, southwest of Cairo, five protesters have been killed in two days of rioting, security officials said. Police opened fire Tuesday on hundreds who set a courthouse on fire and attacked a police station, demanding the removal of the provincial security chief.
The army was forced to secure several government buildings and prisons, and on Wednesday the security chief was dismissed, security officials said. They spoke on condition of anonymity because they were not authorized to talk to the media.
In the city of Suez, strikes entered a second day on Wednesday. Some 5,000 workers at various state companies - including textile workers, medicine bottle manufacturers, sanitation workers and a firm involved in repairs for ships on the Suez Canal - held separate strikes and protests at their factories.
Traffic at the Suez Canal, a vital international waterway and a top revenue earner for Egypt, was not affected.
"We're not getting our rights," said Ahmed Tantawi, a Public Works employee in Suez. He said workers provide 24-hour service and are exposed to health risks but get only an extra $1.50 a month in hardship compensation. He said there are employees who have worked their entire lives in the department and will retire with a salary equivalent to $200 a month.
In Tahrir Square about 10,000 massed again on Wednesday, the day after a crowd of about a quarter-million proved that they had not lost momentum even as Mubarak clings to power. Visitors snapped pictures and took videos while vendors sold nuts, popcorn, Egyptian flags, sandwiches and drinks.
Nearby, 2,000 more protesters blocked off parliament, several blocks away, chanting slogans for it to be dissolved. A huge caricature of Mubarak hung on the gates of parliament and army troops were on the grounds.
Organizers called for a new "protest of millions" for Friday similar to those that have drawn the largest crowds so far. But in a change of tactic, they want several protests across Cairo instead of only in Tahrir Square downtown, said Khaled Abdel-Hamid, one of the youth organizers.
The Obama administration is trying to keep pressure on Egypt's leaders. White House spokesman Robert Gibbs said Egypt's government had not even met a minimum threshold of reforms demanded by its people and warned that massive protests will continue until changes are made.
Fresh support for the protesters is coming from an unlikely corner - Egypt's state-owned Al-Ahram newspaper. The mouthpiece of successive regimes since the 1950s, the paper has sharply changed the tone of its unrest coverage and is using the word "revolution" to describe the anti-Mubarak demonstrations. The newspaper, Egypt's oldest, previously echoed official statements that called the protesters "outlaws" or "saboteurs" and a "bunch of conspirators."
Efforts by Vice President Suleiman to open a dialogue with protesters over reforms have broken down since the weekend, with youth organizers of the movement deeply suspicious that he plans only superficial changes far short of real democracy. They refuse any talks unless Mubarak steps down first.
Showing growing impatience with the rejection, Suleiman issued a sharp warning that raised the prospect of a renewed crackdown. He told Egyptian newspaper editors late Tuesday that there could be a "coup" unless demonstrators agree to enter negotiations.
Protesters considered the reference to a coup to be a veiled reference to a possible new crackdown. Suleiman, a military man who was intelligence chief before being elevated to vice president amid the crisis, tried to explain the coup remark by saying: "I mean a coup of the regime against itself, or a military coup or an absence of the system. Some force, whether its the army or police or the intelligence agency or the (opposition Muslim) Brotherhood or the youth themselves could carry out 'creative chaos' to end the regime and take power," he said.
"We can't bear this for a long time," Suleiman said of the protests. "There must be an end to this crisis as soon as possible." He said the regime wants to resolve the crisis through dialogue, warning: "We don't want to deal with Egyptian society with police tools."
Officials have made a series of pledges not to attack, harass or arrest the activists, but Suleiman's comments suggested that won't last forever.
Egyptian Foreign Minister Ahmed Aboul Gheit said in an interview with "PBS NewsHour" that there would be chaos if Mubarak stepped down immediately. He warned that if the opposition tried to compose an unconstitutional government, "then maybe the armed forces would feel compelled to intervene in a more drastic manner. Do we want the armed forces to assume the responsibility of stabilizing the nation thru imposing martial law, and army in the streets?"
Suleiman, a close confident of the president, rejected any "end to the regime" including an immediate departure for Mubarak, who says he will serve out the rest of his term until September elections.
Suleiman suggested Egypt was not ready for democracy, and said a government-formed panel of judges, dominated by Mubarak loyalists, would push ahead with recommending its own constitutional amendments to be put to a referendum. Those statements further deepened protesters' skepticism over his intentions.
Still, authorities continued to try to project an image of normalcy. Egypt's most famous tourist attraction, the Pyramids of Giza, reopened to tourists on Wednesday after a 12-day closure. But few came to visit - tens of thousands of foreigners have fled Egypt amid the chaos, taking with them an important facet of the nation's economy.
Meanwhile, the newly appointed culture minister, Gabr Asfour, resigned his post for health reasons, according to government spokesman Magdy Rady.
Associated Press writers Hadeel al-Shalchi, Hamza Hendawi, Paul Schemm, Maggie Hyde and Maamoun Youssef contributed to this report.