The U.S. military says three-thousand-200 American troops from the 82nd Airborne Division have arrived in Baghdad as the first part of a military buildup to help Iraqi security forces fight sectarian violence.
The troops are to be fully operational by February first. They are the first of about 17,000 reinforcements to be sent to Baghdad as part of President Bush's controversial strategy to stabilize the city.
Violence is continuing in the capital. Police say two bomb blasts in Baghdad have killed at least seven people and wounded about 20.
The U.S. military says five more American soldiers and a Marine were killed Saturday in separate incidents north and west of the capital.
The announcements raise the U.S. military death toll on Saturday to 25.
In the deadliest incident, twelve American troops died when their helicopter crashed northeast of Baghdad. The cause of the crash is unclear.
Five American soldiers were killed on Saturday in the Shi'ite holy city Karbala as militia fighters attacked a government building.
Iraqi officials said Sunday that the attackers were dressed in U.S. and Iraqi military uniforms and drove up to the building in black sports utility vehicles like those used by the Americans.
A U.S. spokesman Brigadier General Vincent Brooks says the attack occurred as American and Iraqi military officials were meeting to discuss security arrangements for pilgrims arriving in Karbala for a Shi'ite festival Ashura.