The warning left in the garage of Omar Hameed, Iraqi National Guardsman, showed two bloody swords and a message: "If you don't quit your job in three days, you will be killed."

The next day, Hameed, still recovering from a leg injury after gunmen attacked his patrol, gave his reply in signs he hung in the market of his hometown of Mahmoudiya (search) and on the street leading to his home: "I wash my hands of the Iraqi National Guard (search)."

He said the decision to give up his job, which paid a relatively hefty $190 a month, was easy because he knew the alternative.

"They have killed many people," Hameed said. "They can reach you anywhere. They can easily break into homes to kidnap or kill you."

As the Jan. 30 election (search) approaches, insurgents aiming to wreck Iraq's democratic transformation have been targeting members of the country's fledgling security forces with increasing brutality and precision.

Car bombings, mortar attacks and drive-by shootings have been followed by kidnappings, ambushes, executions and beheadings, with corpses dumped in orchards and on roadsides, sometimes laid out in rows.

The operations show enough sophistication and planning to raise the question of whether insurgents get inside help. Such attacks also continue to undermine efforts to build strong security forces — key to the exit strategy of foreign troops — and have cast doubt on the Iraqi forces' ability to protect themselves, let alone the country.

On Thursday and Friday, 32 bodies were discovered in the northern city of Mosul, bringing the number found in Mosul and surrounding areas to 52 since Nov. 18. At least 11 — nine of them shot execution-style — belonged to security forces. The rest have not been identified.

"It's a continued campaign of threats, intimidation and murder by insurgents to spread fear into the public," said Lt. Col. Paul Hastings, a U.S. military spokesman in Mosul. "Their campaign has been directed at what appears to be Iraqi security forces."

He blamed Saddam Hussein loyalists and Islamic extremists. Since an insurgent uprising in Mosul earlier this month that saw masked gunmen overpowering police and burning and looting some police stations, there had been "accelerated and very deliberate attacks on Iraqi security forces," he added.

Maj. Gen. Anwar Mohammed Amin, the senior Iraqi National Guard official in the northern city of Kirkuk, said the change in techniques showed a highly adaptable and astute enemy.

"They're smart people," he said. "They have planners and they have people experienced in the art of warfare. They make preparations, have weapons and the Internet."

To work around increased security measures, such as barricades around military bases to fend off car bombers, militants have turned to kidnapping or ambushing security forces, he said.

Insurgents also have been able to infiltrate security forces, buying or extorting information and tracking troop movements by monitoring their radio transmissions, he added.

Several police officers and Iraqi soldiers, in some cases senior commanders, have been arrested across Iraq for alleged insurgent ties.

Soldiers returning home from base often are ambushed. Maj. Gen. Rashid Feleih, commander of a special police force dispatched to Mosul after the latest violence there, said insurgents sometimes have people waiting at bus and car terminals to monitor troops getting rides from there.

Last month, insurgents at a fake checkpoint stopped buses carrying U.S.-trained Iraqi soldiers and killed about 50 of them. Investigations were launched into whether the attackers got inside information.

Police have been attacked and dragged from their homes. During the past six months, 60 Iraqi policemen — not including Iraqi National Guardsmen and other security force members — have been killed in the Mosul area, Feleih said.

In Mahmoudiya, where ex-National Guardsman Hameed lives, people describe masked gunmen clutching walkie-talkies and barging into homes, inspecting IDs and searching for guardsmen. One family, whose National Guard son was kidnapped from home, found his body almost a month later in a hospital morgue.

Hameed said that in his neighborhood, the absence of police on the streets adds weight to the militants' threats.

In Mosul, residents and officials talk of fake checkpoints manned by militants who check IDs, single out security personnel and shoot them. Sometimes bodies are mutilated, Feleih said.

Amin in Kirkuk said some security force members in his area received threats and CDs of gruesome beheadings at their homes. In recent weeks, 10 guardsmen were killed in three attacks in his area alone.

His forces have orders to vary their travel and patrol routines and always move in convoys.

The Iraqi National Guard has been involved in several high-profile raids and operations with U.S. forces, making it more visible and more closely associated with the U.S. military.

Though statistics on the ethnic and religious breakdown of Iraqi soldiers are not available, some militants have tried to paint the fight as one pitting Sunni insurgents against Shiite soldiers.

Civilians who escaped the Sunni militant stronghold of Fallujah during the assault on insurgents there claimed some National Guardsmen plastered walls with photos of Grand Ayatollah Ali al-Sistani, a top Shiite cleric, angering Sunni townspeople. Reporters in Fallujah saw photos of Shiite saints tied to the bumpers of some trucks carrying Iraqi security forces.

But officials say National Guardsmen are mostly targeted just for serving in the security forces.

"They think of us all as spies for the Americans," said Hameed, who is Sunni. "In the force, we all wanted to watch out for each other. We were scared and we all joined to make a living."