The goal of the operation, according to the Pentagon, is to root out insurgents from an area northeast of Samarra, which is about 100 kilometers north of Baghdad.
In a briefing, White House spokesman Scott McClellan said the operation is part of an ongoing strategy against "Saddam loyalists."
"Our commanders in the theater have the authorization to make tactical decisions about the operations that they undertake, and there have been a number of operations that have been undertaken over the course of the last several months to really go after the terrorists and the Saddam loyalists who want to return to the past of oppression and tyranny," McClellan said. "So this operation is part of our ongoing efforts to help move forward on the security front."
McClellan denied that the timing of the offensive was linked in any way to flagging U.S. public support for the war effort.
Targeting the Sunni Triangle
According to a Pentagon statement, more than 1,500 U.S., Iraqi, and coalition troops, 200 armored vehicles, and 50 aircraft are participating in the assault, which is expected to last several days. Troops have already uncovered a number of insurgent weapons caches.
Operation Swarmer is only the latest is a series of offensives against Sunni Arab insurgents. The most recent was in early March just west of Samarra.
Samarra is the center of the so-called Sunni triangle, which has been home to insurgent activity for the past three years. This activity has escalated since a major Shi'ite shrine was bombed last month. The bombing plunged the area into sectarian violence, resulting in hundreds of deaths in reprisal attacks.
While Operation Swarmer was occurring, the new Iraqi parliament held its first session. It adjourned after 40 minutes.