The violence has spread from the capital to towns outside of Addis Ababa.
The four died in the town of Bahir Dar, about 400 kilometres northwest of the capital, where police clashed with demonstrators demanding the release of opposition members in police custody, said the state-run Ethiopian News Agency said, quoting police sources.
There was also violence in the Ethiopian towns of Awasa, Gondar, Dessie and Dire Dawa, the government said, but police did not say whether there were any fatalities in these towns.
According to a diplomat, eight people including a soldier were killed in Bahir Dar.
Two other diplomats said two civilians were killed in Dessie, a scene of similar rioting.
The government blames the violence on the opposition Coalition for Unity and Democracy (CUD), which has become increasingly vocal in claims that May 15 elections were rigged by the ruling Ethiopian Peoples’ Revolution Democratic Front (EPRDF) coalition, headed by Prime Minister Meles Zenawi.
“The CUD is responsible for the damage and loss of life that has occurred in the capital in the last three days,” Meles said on state television, in his first declaration since rioting erupted on Tuesday.
“The (CUD) officials who have been arrested will be taken to court,” Meles said without giving a date when they would be charged.
“They are responsible for all these things.”
Federal authorities arrested the entire CUD leadership shortly after the unrest began.
The government has also begun a press clampdown following the violence with the New York-based Committee to Protect Journalists (CPJ) saying Ethiopian authorities have detained two editors and ordered private newspapers to close.
It said Dawit Kebede, the editor-in-chief and Feleke Tibebu, the deputy editor and a reporter of the independent Amharic-language weekly Hadar were arrested on Wednesday and are in Addis Ababa’s central prison but have not been charged.
In addition, police prevented the government-owned printing press from printing private newspapers, most of which failed to appear on news stands this week.
“Police ordered the private weekly Ethiop to stop printing on Tuesday night,” CPJ added.
Last weekend, the CUD called a general strike for November 14 and also for a boycott state media and products made by government firms.
The CUD, which officially won 109 of about 370 parliamentary seats in the polls, is also boycotting the legislature and its deputies were last month stripped of their parliamentary immunity amid allegations of plotting to overthrow the government.
This week’s protests are the second wave of violence to hit the poverty-stricken Horn of African nation, home to about 70 million people, since the May elections. In June, at least 37 people were killed in riots in the capital.
The African Union and the United States have called for calm and urged both sides to resolve their problems through dialogue.
Meanwhile Zenawi on Friday said his troops are ready to “take necessary measures” to defend the country’s sovereignty in escalating tensions with Eritrea over an unresolved border dispute.
The UN Mission to Ethiopia and Eritrea (UNMEE) reported re-positioning of troops and armament on both sides of the frontier Wednesday, with one official describing the situation there as having deteriorated from “stable” to “tense.”
A peace deal signed in 2000, under intense international pressure, required both countries to accept a new border demarcation drawn up by an international panel.