Egypt's government said on Wednesday it would not allow any demonstrations and protesters would be detained, as it sought to draw a line under the biggest protests of President Hosni Mubarak's rule.
Two protesters and one policeman were killed in clashes that erupted on Tuesday in several Egyptian cities. A fourth protestor died in hospital on Wednesday.
Gharib Abdelaziz Abdellatif, 45, died in Suez, east of Cairo, the source said. Two other protesters died in Suez on Tuesday due to rubber bullets. A police officer was killed on Tuesday in Cairo as a result of a stone hitting his head.
"No provocative movements or protest gatherings or organizing marches or demonstrations will be allowed, and immediate legal procedures will be taken and participants will be handed over to investigating authorities," the state news agency MENA cited the Interior Ministry as saying.
Some 20,000 demonstrators, complaining of poverty, corruption and repression and inspired by this month's downfall of the president of Tunisia, turned out to demand Mubarak step down.
Police used teargas to break up the protests and calm had returned to Cairo and other cities by Wednesday morning.