Militants fired several mortars or rockets at Baghdad's fortified Green Zone government district today shortly after US Vice President Joe Biden flew in to keep pressure on Iraqi leaders to make political compromises.
Iraqi police said two out of four suspected mortar rounds landed near the sprawling U.S. embassy compound in the Green Zone, but did not hit it. Mr Biden had met with the US ambassador, Christopher Hill, and the top US military commander, General Ray Odierno, just before the mortar strikes.
His precise location was being kept secret for security reasons.
It was Mr Biden's second trip to Iraq in three months, and the visit signalled that the Obama administration is anxious to resolve long-standing disputes between Kurdish, Shia and Sunni Arab communities over land and oil that US officials fear could yet rip apart the country.
Violence has dropped sharply in Iraq since the height of a wave of sectarian killings in 2006, due in part to a "surge" of tens of thousands of US troops, but the security gains have not been matched by much political progress.
The security gains themselves remain fragile, as evidenced by today rocket and mortar attacks and two giant truck bombs on August 19th that killed 95 people at the Iraqi foreign and finance ministries and shattered public confidence in Iraq's police and military.
Since 2006, Washington has pressed Iraq's Kurdish, and Shia and Sunni Arab leaders, with little success, to put aside differences and compromise on issues such as a new oil law to manage the world's third-largest oil reserves.
But with US combat operations due to end in Iraq by August 2010, the United States is running out of time and influence among Iraq's leaders to achieve its goal - to leave behind a relatively stable Iraq that can resist efforts by neighbouring Shia Iran to meddle in its affairs.
Reuters