With the streets of Baghdad and other major cities largely emptied by a daytime curfew, imams across Iraq on Friday called for an end to the sectarian rioting that has left more than 140 people dead over the past few days, as political leaders held emergency meetings to contain the crisis.
Increased violence erupted Wednesday morning when a powerful explosion shattered the golden dome of the Askariya Shrine in Samarra, one of Iraq's most revered Shiite sites. The blast set off three days of sectarian fury in which mobs formed across the country to chant for revenge and attacked dozens of Sunni mosques.
Here's a look at the attacks, reaction and the danger of full-blown civil war.
What happens next?
The issue now is whether Iraq will plunge into outright civil war, find some political way to coexist, or whether this kind of low- to middle-intensity civil conflict continues. A lot depends on Shiite leaders, especially Grand Ayatollah Ali al-Sistani, the top religious leader, and the nationalist cleric Muqtada al-Sadr. Their challenge is to control and channel the anger, to let it be expressed but not get out of control.
How was the latest bombing different?
Such a brazen attack on a Shiite shrine - which will be seen as a direct assault on the identity and rights of an entire community - takes the danger of a civil conflict to a new level. It has produced bigger protests than the killing of humans. Holy places in the Middle East are very special for the people who consider them sacred. They are a vital part of the way that people see themselves.
How have Shiite and Sunni leaders responded?
Top Shiite political leader Abdul-Aziz al-Hakim, head of the Supreme Council for the Islamic Revolution in Iraq, condemned the killings as well as attacks on Sunni or Shiite mosques. A Sunni spokesman, Dhafer al-Ani, called al-Hakim's statement "a step on the road of healing the wounds." But he said his Iraqi Accordance Front was waiting for an apology for failing to protect Sunni mosques from reprisal attacks.
What security measures were being taken?
Iraqi Prime Minister Ibrahim al-Jaafari, a Shiite, said he had deployed Iraqi armed forces in areas of friction and banned all vehicles from entering or leaving the capital other than police cars, ambulances and government trucks. He reached out to Sunnis and Shiites, promising to rebuild the Shiites' Askariya Shrine and damaged Sunni mosques. Friday's daytime curfew appeared to have blunted the surge in sectarian violence and was extended for a second straight day.
What is the status on discussions to form a new government?
Two months after national elections, Iraq's political parties are repeating the tortuous wrangling that epitomized negotiations last year over forming a transitional government and writing the draft constitution. After the bombing in Samarra, the largest Sunni Arab bloc in Parliament has pulled out of talks with the main Shiite Arab coalition talks, saying they will not resume negotiations until the government apologizes for attacks on Sunni mosques and meets other demands.
Are U.S. efforts to form a permanent government there progressing?
Secretary of State Condoleezza Rice on Friday blamed "people who are trying to stoke civil war in Iraq" for provoking the violence as an 11th-hour play to derail political consensus. She remains confident Iraqis "are devoted to, dedicated to, the formation of a national unity government."
What is the U.S. reaction to the violence?
President Bush on Friday called for calm in Iraq. "This is a moment of choosing for the Iraqi people," he said. "We can expect the coming days will be intense. Iraq remains a serious situation, but I'm optimistic because the Iraqi people have spoken and make their intentions clear. They want their freedom. They want their country to be a democracy."
How does this affect coalition plans?
The chaos that has overtaken Iraq is threatening hopes that starting significant troop withdrawals might be possible in the coming months. At the moment, neither of the two elements needed before a foreign withdrawal can happen are in place: There is neither a functioning government nor security.
What's the worst that could happen?
A full-blown civil war, which would destroy the chances of the elected Shiite-led Parliament forming a government, and could lead to the break-up of the country. That would result in even more instability and violence across the Middle East and beyond. That is why most Iraqis, of all sides, do not want a civil war - and why some extremists do, and are trying as hard as they can to make it happen.
Isn't Iraq already in a civil war?
The fact is that there has been a war in Iraq for the best part of three years. But everyone in Iraq - and across the Middle East - knows that a full-blown civil war would be much worse. Its responsible leaders have recognized the danger. Jalal Talabani, the president of Iraq, was worried enough to go on television this week to warn how dangerous such a conflict would be.
Sources: BBC Online, Associated Press and the New York Times