BAQUBAH, IRAQ — The Iraqi government's most ambitious effort yet to assert its authority over long-troubled parts of the country began Tuesday with polite requests to search homes in and near this capital of Diyala province.
It was a modest and carefully prepared launch of a campaign that Iraqi commanders say will make use of nearly 30,000 Iraqi troops and eventually stretch across a region east of Baghdad that is roughly the size of Maryland. The government's previous crackdowns focused on individual cities.
"The mission is to clear the whole province . . . of terrorists and outlaws and to bring back security and stability," Lt. Gen. Ali Gaidan Najid, commander of the Iraqi ground forces, said at a meeting to coordinate operations with U.S. forces.
Iraqi soldiers and national police encountered no resistance as they knocked on doors in Baqubah and the town of Khan Bani Saad, about 15 miles south. But this is well-trod ground for the Iraqi forces and their U.S. counterparts, who have conducted repeated operations in the area since last year.
The troops will face a more serious test when they push into the province's hinterlands, where Sunni Arab militants loyal to insurgent groups including Al Qaeda in Iraq have found sanctuary since they were pushed out of the city of Fallouja, west of Baghdad in Anbar province, in 2004.
The U.S. military believes many insurgent leaders have already fled their hide-outs since Prime Minister Nouri Maliki announced at the end of June that he was sending reinforcements to Diyala. But they typically leave behind roads riddled with mines, houses rigged to explode and suicide bombers armed with explosives vests.
Diyala, an ethnically and religiously mixed region stretching from the eastern outskirts of Baghdad to the Iranian border, has long been a hotbed of violence. Al Qaeda in Iraq declared Baqubah the capital of its self-styled Islamic caliphate, and the group's founding leader, Abu Musab Zarqawi, died in a U.S. airstrike near the city in June 2006.
A series of U.S.-led campaigns, which began last year, restored a measure of calm to the main cities and towns along the central portion of the Diyala River, a region of rich farmland laced with canals that was long the breadbasket of Iraq.
