BAGHDAD, Iraq (AP) - The scale and sophistication of militant attacks in Iraq are steadily increasing, with coordinated strikes and complicated ambushes that increasingly hit their targets, officials and analysts said Wednesday.
The spike in bloodshed - more than 200 dead in four days - has stifled American hopes that the transfer of sovereignty and the prospect of a democratic vote in four months could take the steam out of the uprising and pave the way for a reduction in U.S. troops.
Instead, there are signs the Americans and their Iraqi allies are facing an enemy more determined than ever. Insurgents have learned from past mistakes and shifted strategy, cooperating more closely with each other and devising new ways to put their relatively simple arsenal to treacherous use.
``More thought is going into the execution of the attacks,'' said Lt. Col. Paul Hastings of Task Force Olympia, which is trying to bring stability to a swath of northeastern Iraq.
Militants now follow up roadside bomb attacks with a deluge of rocket-propelled grenades instead of fleeing, or fire off mortar rounds to lure soldiers out of their base and into freshly laid mine fields, military commanders say.
In a July attack in Samarra, for example, militants detonated a car bomb and then hammered a military headquarters with a mortar barrage as troops fled the building. Five American soldiers died.
At least 47 people were killed in a car bombing in Baghdad on Tuesday targeting would-be police recruits, the deadliest single strike in the capital in six months.
``The enemy has been able to construct IEDs (Improvised Explosive Devices) that are more complex, include more rounds in the form of a ``daisy chain,'' and tend to have a higher lethality,'' said Maj. Neal O'Brien of the Army's 1st Infantry Division.
O'Brien also said that an increase in the use of car bombs in the last two months coincided with an influx of foreign fighters with the bomb-making know-how in July.
``They graduated to more coordinated attacks,'' he said.
On Sunday, militants in Baghdad struck the U.S.-guarded Green Zone - the seat of the Iraqi government and the U.S. Embassy - with their biggest mortar and rocket barrage to date, many of them showing signs of careful aim.
Hours later, guerrillas used a car bomb to disable a U.S. patrol on a main Baghdad thoroughfare before detonating a second car bomb that wrecked a Bradley fighting vehicle sent to assist the patrol. They then opened fire on the wounded crewmen as they fled the vehicle.
``The set of attacks that occurred over the weekend were definitely more simultaneous than in the past,'' said Lt. Col. Steven Boylan, spokesman for coalition forces in Baghdad.
Analysts say the plethora of armed groups behind the insurgency are increasingly working together.
``As time goes on, various gangs get together and it does become more coordinated,'' said Judith Kipper, a Middle East expert at the U.S.-based Council on Foreign Relations. ``Groups start small, get know-how and become more lethal over time.''
American commanders, however, insist the stepped-up attacks and the possibility of increased cooperation among militant groups are signs that the insurgents have realized time is running out for them with the onset of elections in January.
``There is a level of desperation associated with the anti-Iraqi forces, they absolutely don't want to see free elections and reconstruction projects work,'' Hastings said.
But the attacks have fueled a growing backlash against the United States and interim Iraqi Prime Minster Ayad Allawi.
``The situation is getting worse day after day and the American are still in the streets,'' said Kawakib Butris, 40, a supermarket worker in Baghdad. ``This government didn't ensure the simplest things to us like security, electricity and other services.''
In response to the growing violence, the Bush administration announced plans this week to divert about $3.5 billion in Iraq reconstruction funds for security and the training of Iraqi forces.
NATO, however, moved close to an agreement on sending hundreds of military instructors to Iraq, with France and the United States narrowing their differences Wednesday over the mission to run a training center for the country's new armed forces.
The plan will likely entail the deployment of 200-300 NATO instructors to Iraq and would complement a much larger U.S.-led operation to build new Iraqi armed forces, which are expected to total 260,000.
Iraqi police and national guardsmen have been the focus of many of the recent attacks, creating a challenge for the United States and Allawi as they strive to strengthen the Iraqi security forces.
The ferocity of the insurgency has also raised new doubts about how effectively Washington and Allawi can carry off the elections - and whether they will be able to wrest control of rebel strongholds such as Fallujah and Ramadi in time to include the cities in the process.
A full-fledged assault may be the only way to restore state authority to Fallujah and Ramadi, even though such a get-tough approach risks alienating the population.
Iraqis, a mostly conservative people, have been deeply angered by some of the practices of the U.S. military, like raiding homes and detaining women, and their failure to restore security more than a year after Saddam Hussein was ousted. While viewing the Americans as infidels or crusaders who want to destroy Islam, many have been won over by what they see as the piety and devotion of Islamic-oriented insurgents.
In places like Fallujah, a hotbed of resistance west of Baghdad, the insurgents have endeared themselves to the local population by spearheading a religious revival and taking over some law enforcement tasks.
``I was very optimistic when the Americans entered Iraq ... but then I was so shocked by their practices that I even joined Fallujah residents in their war against them,'' said Haqi Esmaiel Ibrahim, 25, an accountant at a Baghdad stationery store. ``Because of the bad security situation and kidnap cases, I had to make my two sisters quit school and stay at home.''
The Americans recently launched a series of military operations and opened negotiations with religious and tribal leaders to retake several cities that have fallen into rebel hands, yielding some positive results.
U.S. troops ended their siege of the northwest city of Tal Afar on Tuesday, saying they had cleared it of militants after 12 days of fighting killed dozens of people. The siege ended soon after neighboring Turkey said it would stop cooperating with U.S. forces in Iraq if ethnic Turks continued to be harmed in the crackdown.
On Wednesday, militants fired a rocket-propelled grenade at U.S. and Iraqi soldiers guarding a council building in Samarra, 60 miles north of Baghdad. The assault came just days after the Americans negotiated a deal with local leaders to enter the city without risk of attack.
Associated Press reporter Sinan Salaheddin contributed to this report.