The fresh troops from the Army's 5th Battalion, 20th Infantry Regiment — equipped with Stryker armored vehicles — joined 3,500 U.S. and 20,000 Iraqi soldiers already in Diyala, where insurgents have stepped up attacks as violence appears to be ebbing in Baghdad.
U.S. commanders said they had been planning to fan out from Baghdad into communities around the capital, such as Baqouba 35 miles to the northeast, to go after insurgents and clandestine workshops that rig car bombs used in attacks in the capital.
"This is not a haphazard fire drill to save the house from burning," Maj. Gen. Benjamin Mixon, commander of U.S. forces in northern Iraq, told The Associated Press. "We began looking at this several months ago in support of the Baghdad plan. We knew the surrounding provinces would be in play."
The 5th Battalion's move occurred as more than 20,000 U.S. troops are pouring into Baghdad seeking to end the bombings, kidnappings and execution-style killings that paralyzed the Iraqi government and threatened the nation with all-out sectarian war.
As U.S. troops pressed the crackdown in the capital, two roadside bombs killed two American soldiers and wounded four Tuesday, the military reported.
With sectarian bloodshed ebbing in Baghdad, attacks on U.S. troops in Diyala have risen 70 percent since summer, according to U.S. figures.
Over the weekend, gunmen believed to be Sunni extremists raided a farming community outside the Diyala city of Muqdadiyah, setting fire to at least 15 houses, slaughtering livestock and driving off the residents, the U.S. military said Tuesday. It quoted residents as saying they tried to defend their homes but fled after they ran out of ammunition.
U.S. officials attribute the rise to Sunni insurgents who fled the capital to areas where they have support from al Qaeda and loyalists of Saddam Hussein's ousted regime.
The former al Qaeda in Iraq leader, Abu Musab al-Zarqawi, was killed in a U.S. airstrike in Baqouba last June. Since then, the Islamic State of Iraq, another group with links to al Qaeda, has claimed Baqouba as capital of its self-proclaimed shadow government.
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