The government imposed the curfew on vehicles and pedestrians, saying it will go through the morning of October 1.
The government declined to say why the curfew was put in place.
The U.S. military today said that U.S. forces had detained a security guard at the home of Adnan Dulaymi, the leader of Iraq's leading Sunni political bloc.
The military said the man was suspected of plotting an attack on the Green Zone, which houses Iraqi government offices and foreign diplomats.
Meanwhile, the governor of Iraq's southern city of Al-Basrah says that Iraqi police tried to kill him in an ambush today.
Al-Basrah Governor Muhammad Musbih al-Wa'ili today said that the alleged plotters are all officers in the Major Crimes Department. He said he will seek legal action against them.
COALITION MEMBERS: In addition to the United States, 28 countries are Multi-National Force-Iraq (MNF-I) contributors as of May 31, 2006: Albania, Armenia, Australia, Azerbaijan, Bosnia-Herzegovina, Bulgaria, the Czech Republic, Denmark, El Salvador, Estonia, Georgia, Italy, Japan, Kazakhstan, Latvia, Lithuania, Macedonia, Moldova, Mongolia, the Netherlands, Poland, Portugal, Romania, Singapore, Slovakia, South Korea, Ukraine, and the United Kingdom. Fiji is participating as part of the UN mission in Iraq. Hungary, Iceland, Slovenia, and Turkey are NATO countries supporting Iraqi stability operations but are not part of MNF-I.
NON-U.S. MILITARY PERSONNEL IN IRAQ: United Kingdom, 8,000 as of May 26, 2006; South Korea, 3,237 as of May 9, 2006; Italy, 2,900 as of April 27, 2006; Poland, 900 as of May 30, 2006; Australia, 900 as of March 28, 2006; Georgia, 900 as of March 24, 2006; Romania, 860 as of April 27, 2006; Japan, 600 as of May 30, 2006; Denmark, 530 as of May 23, 2006; All others, 1,140.
(Source: The Washington-based Brooking Institution’s Iraq Index of June 15, 2006)
RADIO FREE IRAQ: To visit the Arab-language website of RFE/RL's Radio Free Iraq, click here.