The story of the kidnapped four-year-old was unbelievably shocking. After his parents failed to find the money for a £5,000 ransom, they opened their front door to find a tray with a cover; under the cover was the boy, grilled on a bed of rice in the style of quzi, an Iraqi lamb dish.

The story — related by a caller to al-Mustakillah television — proved impossible to verify. But in a land beset by car bombings and murders, stories such as this spread like wildfire. The rumours are fantastical and absurd and are meant to terrify.

Firas Jezani, 18, heard about a body dumped at a park in the Mansour district of Baghdad. Inside the bloated belly was the head of the dead man’s son.

Marwan Khalid, a 22-year-old college student, shared a similarly ghastly story. Fellow students told him that two professors at Mustansariyah University in Baghdad were kidnapped. One body was found with a dog’s head stitched on at the neck and the other with a donkey’s. Mr Khalid is well educated and doubted the story but it helped to increase his fear of terrorists, criminals and militias and he decided to get out. He quit university in 2005 and fled to Jordan for a year.

Gripped by fear, people believe the apocryphal tales, accepting that anything could happen in Baghdad after the fall of Saddam Hussein. A few months ago shopowners were frightened to display cucumbers and tomatoes on their stands because they thought that Sunni and Shia militants considered them representative of male and female genitalia.

The rumour mill perhaps helps to explain a new poll showing pessimism growing among Iraqis about the future.

Only 18 per cent had faith in the US-led coalition forces, while 78 per cent opposed their presence; 69 per cent said coalition forces made security worse and 51 per cent said violence against coalition soldiers was justified. The survey was sponsored by the BBC, ABC News, ARD German television and USA Today.

The US military, wary of the mood on the street, monitors the tall tales circulating and an in-house weekly paper, the Baghdad Mosquito, reports them. “We are looking for incorrect information on the street,” said Lieutenant-Colonel Christopher Garver, a US military spokesman. He recalled one recent story that claimed the Iraqi Government had enough electricity for powercut-plagued Baghdad but was hoarding it.

The challenge is to dispel the faulty notion, but the Americans and the Iraqi Government have a tough time. People are credulous about allegations involving abuses committed by the US Army or the Iraqi Government.

“Unfortunately that kind of thing [abuse] has happened and makes the rumour seem more believable,” Lieutenant-Colonel Garver said.

Bodies bearing signs of torture are dumped daily, and with criminal gangs and militants lurking, people lap up the nightmarish visions. Lieutenant-Colonel Garver said that one factor contributing to the stories was the country’s poor communications infrastructure. Irregular land lines and mobile phone networks fuel the evolution of these tales.

Aziz Jabur, a political scientist at Mustansariyah University, said: “There is a dirty war being conducted against our country.” He called the stories a form of psychological war. “To horrify people by rumours is an ancient practice.”

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