Obsolete

The executions are carried out at dawn on Haqlania bridge, the entrance to Haditha. A small crowd usually turns up to watch even though the killings are filmed and made available on DVD in the market the same afternoon.

One of last week's victims was a young man in a black tracksuit. Like the others he was left on his belly by the blue iron railings at the bridge's southern end. His severed head rested on his back, facing Baghdad. Children cheered when they heard that the next day's spectacle would be a double bill: two decapitations. A man named Watban and his brother had been found guilty of spying.

A three-day visit by a reporter working for the Guardian last week established what neither the Iraqi government nor the US military has admitted: Haditha, a farming town of 90,000 people by the Euphrates river, is an insurgent citadel.

That Islamist guerrillas were active in the area was no secret but only now has the extent of their control been revealed. They are the sole authority, running the town's security, administration and communications.

A three-hour drive north from Baghdad, under the nose of an American base, it is a miniature Taliban-like state. Insurgents decide who lives and dies, which salaries get paid, what people wear, what they watch and listen to.

Haditha exposes the limitations of the Iraqi state and US power on the day when the political process is supposed to make a great leap - a draft constitution finalised and approved by midnight tonight.

There is no fighting here because there is no one to challenge the Islamists. The police station and municipal offices were destroyed last year and US marines make only fleeting visits every few months.

Two groups share power. Ansar al-Sunna is a largely homegrown organisation, though its leader in Haditha is said to be foreign. Al-Qaida in Iraq, known locally by its old name Tawhid al-Jihad, is led by the Jordanian-born Abu Musab al-Zarqawi. There was a rumour that Zarqawi, Washington's most wanted militant after Osama bin Laden, visited early last week. True or not, residents wanted to believe they had hosted such a celebrity.

A year ago Haditha was just another sleepy town in western Anbar province, deep in the Sunni triangle and suspicious of the Shia-led government in Baghdad but no insurgent hotbed.

Then, say residents, arrived mostly Shia police with heavyhanded behaviour. "That's how it began," said one man. Attacks against the police escalated until they fled, creating a vacuum filled by insurgents.

Alcohol and music deemed unIslamic were banned, women were told to wear headscarves and relations between the sexes were closely monitored. The mobile phone network was shut down but insurgents retained their walkie-talkies and satellite phones. Right-hand lanes are reserved for their vehicles.

Now insurgents earn praise from residents for allegedly pressuring managers to supply electricity almost 24 hours a day, a luxury denied the rest of Iraq.

The court caters solely for divorces and marriages. Alleged criminals are punished in the market. The Guardian witnessed a headmaster accused of adultery whipped 190 times with cables. Children laughed as he sobbed and his robe turned crimson.

Two men who robbed a foreign exchange shop were splayed on the ground. Masked men stood on their hands while others broke their arms with rocks. The shopkeeper offered the insurgents a reward but they declined.

DVDs of beheadings on the bridge are distributed free in the souk. Children prefer them to cartoons. "They should not watch such things," said one grandfather, but parents appeared not to object.

One DVD features a young, blond muscular man who had been disembowelled. He was said to have been a member of a six-strong US sniper team ambushed and killed on August 1. Residents said he had been paraded in town before being executed.

The constitution talks, the referendum due in October, the election due in December: all are deemed collaboration punishable by death. The task now is to bleed the Americans and destabilise the government. Some call that nihilism. Haditha calls it the future.