Three large, coordinated attacks in the central Iraqi city of Karbala have killed at least six coalition soldiers - two Thai and four Bulgarians - and injured at least 37 more. Some reports put the number of wounded at more than 100. The head of a multi-national force in southern Iraq, Polish general Andrzej Tyszkiewicz, said Saturday's bomb attacks in Karbala were part of a massive, coordinated strike against coalition forces.
The attacks on coalition military facilities in Karbala came within minutes of each other.
The attackers used car bombs at all three sites. In the deadliest assault, they also launched mortar rounds. Another military camp was hit with two car bombs and small arms fire.
The third coalition base to be hit was located in the same place as an Iraqi police station, and many of the casualties there are believed to be police officers. Karbala is controlled by a multi-national force under Polish command.
News reports from the city say the attacks also damaged a government building and a university, wounding a number of students.
Karbala is located about 100 kilometers southwest of Baghdad and is home to several of the holiest shrines in Shi'ite Islam.
The bombings in Karbala are believed to be the most coordinated, extensive and deadly assault on coalition targets since the capture of deposed Iraqi leader Saddam Hussein two weeks ago.
The U.S. military deputy chief of operations, Brigadier General Mike Kimmitt, says it appears that the anti-coalition resistance is fairly well organized.
"We do believe that there are cells throughout the country, primarily concentrated in the larger cities, that have some loose form of coordination," he said. "Is it a centrally organized command-and-control network, that if you cut off the head of the snake, everything underneath it collapses? We don't think it's that. At the same time, are they loose-knit, informal, uncoordinated? We don't think it's that. It's somewhere in between that, where there's some form of loose coordination between them. That is one of those puzzles that our analysts keep working on every day."
Over the last few days, there have been a series of mortar and rocket attacks in Baghdad and surrounding cities in the so-called Sunni Triangle, where support for Saddam Hussein remains highest.
But the violence in Karbala and several recent attacks in northern Iraq show that the insurgency is hardly limited to Saddam's stronghold.