INSURGENTS in the rebel Iraqi city of Falluja claimed yesterday that they had added chemicals to mortar rounds and missiles that they intend to fire at American forces preparing for an all-out assault.

Cell commanders said some of the weapons could cause high-temperature fireballs and others were filled with cyanide.

A military committee made up of former officers in Saddam Hussein’s army — among them experts on chemicals and guerrilla warfare — is said to have been organising forces in Falluja and planning tactics.

The committee is understood to include members of all the main insurgent groups, including that of Abu Musab alZarqawi, the terrorist leader behind the beheading of the British engineer Ken Bigley and many other atrocities.

It was formed after a US military offensive against Falluja in April “to help the insurgents learn from the mistakes of that period and to prepare and enhance the military plan for the next round”, one commander said.

Yesterday Sheikh Mahdi al-Sumaidi, a Sunni cleric in Baghdad, warned the Americans and Iraqi government forces against attacking Faluja. He said they risked incurring a fatwa, or binding religious decree, that would command Muslims to launch street protests and a campaign of civil disobedience.

But US forces continued preparations for the widely expected offensive, with jets and artillery pounding targets in the city. A US marine at a base near Falluja described it as the heaviest artillery bombardment he had heard in two months.

Residents said that at least five people died in the eastern Askari district of Falluja on Friday night. Yesterday afternoon about a dozen airstrikes hit a southeastern district of the city.

American military officials have claimed that there are up to 5,0000 Islamic militants, Saddam loyalists and criminals barricaded in the town “We’re gearing up to do an operation and when we’re told to go, we’ll go,” said Brigadier General Dennis Hejlik, deputy commander of the 1st Marine Expeditionary Force, at a camp near Falluja. “When we do go, we’ll whack them.”

According to the insurgents, however, many of their most experienced fighters have already left the city.

The American military emphasised that the final order to attack should come from Iyad Allawi, the Iraqi prime minister, who has told the people of Falluja to hand over the followers of al-Zarqawi.

In a separate incident yesterday seven people were killed when a car bomb exploded outside the offices of the Al-Arabiya television network in Baghdad. Several technicians and drivers working for the channel were injured.

A group calling itself the 1920 Brigades claimed responsibility and said on an Islamic website that the attack had brought down the offices of “the mouthpiece of the American occupation in Iraq”. More attacks would follow, it said.

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