The small amount of deadly nerve agent sarin dispersed by a shell that exploded near a U.S. military convoy apparently was left over from Saddam Hussein's banned chemical arsenal built up two decades ago.

President Bush and Congress have so far provided $191 billion for wars in Iraq and Afghanistan and defensive military operations at home, and about two-thirds of the money has been spent or is owed, White House figures show.

The Bush administration's decision to pull back U.S. Marines from the brink of a major assault against Fallujah — and use Iraqi fighters in their place — is a calculated risk born of having few good options.

In Karbala, American troops sped into the city and seized a government building that also was being occupied by fighters loyal to cleric Muqtada al-Sadr.