As the 10,000-troop mission to take back the volatile and extremely dangerous province intensified in its fourth day, so have concerns about keeping al Qaeda fighters on the run. The terrorist fighters and their allies already have been run out of Fallujah and Ramadi in Anbar province, only to regroup in Diyala's capital of Baqouba and surrounding districts.
The U.S. ground forces commander, Lt. Gen. Raymond Odierno, said more than three-quarters of Baqouba's al Qaeda leadership fled before the Americans moved into the city this week. At the time, drone observer planes spotted fighters planting dozens of roadside bombs on the main highway into Baqouba.
Brig. Gen. Mick Bednarek, assistant commander for operations with the 25th Infantry Division, estimated that several hundred low-level al Qaeda fighters remained.
"They're clearly in hiding, no question about it. But they're a hardline group of fighters who have no intention of leaving, and they want to kill as many coalition and Iraqi security forces as they possibly can," Bednarek said Friday.
"It's 24/7 for us here, and it's probably the same for our adversary as well," he said. "It's house-to-house, block to block, street to street, sewer to sewer — and it's also cars, vans — we're searching every one of them."
Meanwhile, Prime Minister Nouri al Maliki's government is also under threat from within. After dozens of interviews with Iraqi political leaders both inside and outside the government, it's clear a broad-based movement is underway to bring down al-Maliki, reports CBS News chief foreign correspondent Lara Logan.
Called the "Iraq Project," the movement's manifesto outlines a plan to overthrow al-Maliki using constitutional means: a no-confidence vote in the Iraqi parliament that will force the prime minister to resign.
In other developments:
An Associated Press employee in Baqouba reported heavy fighting as U.S. troops swept into three eastern neighborhoods in Friday's operation, which began after U.S. forces warned residents to leave or stay indoors.
The American military said the 17 al Qaeda fighters were killed trying to flee past Iraqi security blockades on the road to Khalis, a predominantly Shiite city northeast of Baqouba.
Earlier this week, creeping house-to-house through western Baqouba, U.S. soldiers made a startling discovery: a suspected al Qaeda field hospital stocked with oxygen tanks, heart defibrillators and other medical equipment.
The find displayed al Qaeda's sophisticated support network in Baqouba, a mostly Sunni town of about 300,000 people, located 35 miles north of Baghdad.
That may presage great problems in an outright defeat of al Qaeda even if U.S. forces succeed in ousting the group from Baqouba. The city has received little aid or other services from the central government, which feared supplies would end up in al Qaeda hands.
As the al Qaeda field hospital proved, much assistance did bypass residents and found its way to the terrorist organization. Until trust is mended, U.S. military commanders say, any success they have in this offensive could be lost on a city unable or unwilling to reconcile sectarian differences.
Historically a mixed province, Diyala has become predominantly Sunni as Shiites fled an influx of Sunni militants from Anbar province. The militants were welcomed by many of Saddam Hussein's former Baath party members.
The shifting population balance only increased tension between local Sunni tribal leaders and the Shiite-dominated federal government in Baghdad.
"There are a multitude of systematic functions that aren't working," said Maj. Robbie Parke, 36, of Rapid City, S.D., a spokesman for the 3rd Brigade, 2nd Infantry Division. "The Iraqi government has to say, `Look, Baqouba is in trouble, and we need to help.'"
So far that has not happened, U.S. officials say. But there are signs of hope.
"The (Iraqi) government is very immature, but they're getting better and saying the right things. We've got to hold them to that," said Odierno.
He spoke to AP during a trip to Baqouba on Thursday as American forces began in earnest to squeeze al Qaeda, Sunni insurgents and Shiite militiamen after the arrival of the final brigade of an additional 30,000 troops dispatched by President Bush.
Diyala province is one of a quartet of operations targeting militants entrenched in the so-called "belts" of Baghdad — regions on the capital's flanks where mostly Sunni insurgents are believed to have based car-bomb factories, weapons stashes and militant safe houses.
High-level U.S. military officials and diplomats are exerting pressure on the Shiite-led government to back national reconciliation and ensure that basic services are restored in Baqouba, Odierno said. Those measures are needed to earn public trust and sustain any U.S. military successes here, he said.
"It goes all the way to the prime minister, and they've promised to do this thing," Odierno told midlevel U.S. commanders involved in the fighting here. "It's my job to hold their feet to the fire, because we're not going to waste this (military) effort — and we're not going to allow al Qaeda to come back here."
Baqouba, the largest consolidated U.S. military effort in Iraq right now, follows the same strategy as the four-month-old Baghdad security plan: U.S. forces clear militants in an effort to allow local Iraqi politicians to regain control of their city. The maintenance — keeping insurgents out for good — will be left to Iraqi security forces.
But U.S. commanders acknowledge that Baqouba's prognosis is tenuous even without al Qaeda unless Iraqis themselves can get a grip on security issues and put aside sectarian divisions.
"Sure, there's tension between Shiites and al Qaeda. But once we get rid of al Qaeda here, we have to see whether there remains Shiite-Sunni tension," Odierno said. He also sought to reassure Sunnis that extremists from their sect were not the only ones responsible for Baqouba's spike in violence.
"The real thing here is our ability to hold and control these areas (once the major fighting is over)," Odierno said. "We'll have to go into Shiite areas as well, to see if there are any extremists there fueling the tension."
In recent months, the Baqouba police chief and the head of the 5th Iraqi Army division, which is in charge of all of Diyala province, both were fired on suspicion they were fueling sectarian tension, said Col. David Sutherland, 45, from Toledo, Ohio. Several members of a Shiite death squad were discovered serving in an Iraqi battalion in Baqouba in February, and were also removed from duty, he said.
The 5th Division is the only Iraqi Army unit in the country that has not been transferred back to full Iraqi ground force control, U.S. officials said.
"They're minimally equipped," said Bednarek. "It takes a while to get them up to the level of proficiency to perform a difficult role against a sophisticated enemy — al Qaeda."