The protests calling for President Hosni Mubarak's ouster have been spreading since Tuesday outside of Cairo's Tahrir Square, where they have been concentrated for the past week. On Wednesday, demonstrators also gathered at parliament, the Cabinet and the Health Ministry buildings, all a few blocks from the square. Prime Minister Ahmed Shafiq was working out of the Civil Aviation Ministry on the other side of the city because his office was blocked by protesters.

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 Tuesday were taken by protesters as a thinly veiled threat of another crackdown.

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.

"They 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.