British dig in for siege of Basra

British forces were digging in around this strategic city today as the push to take and secure it turned into a siege.

Allied commanders have decided an all-out advance into the densely-populated areas would constitute too heavy a risk for troops and civilians who have already been enraged by losses inflicted by shelling and aerial attacks.

Some armoured units have made probing moves into the sprawling suburbs and industrial areas, but the heart of the city remains firmly in the hands of fighters believed to be irregulars loyal to Saddam Hussein. Intelligence reports indicate that these so-called Martyr Battalion troops include Afghans and Islamic militants trained within the al Qaeda network. Fanatics who support Osama bin Laden are thought to have volunteered to fight for Saddam in the months before the allied invasion of Iraq.

This leaves coalition commanders with a nightmarish problem. The irregulars, or Fedayeen, are using civilians for cover and are operating from homes, schools and hospitals.

As British troops of the 7th Armoured Brigade took up positions around the city, they were targeted by hit-and-run mortar and rocket-propelled grenade attacks. An American unit near here sent up an unmanned reconnaissance aircraft to try to locate the source of the incoming fire, but the Iraqis managed to shoot it down. This indicated that their anti-aircraft capability has not been entirely destroyed.

Like everywhere else on the road to Baghdad, Basra has proved far more resilient than anyone expected.

After almost a week on the outskirts of the city, I have watched numerous attempts to take and secure the city but the reality is that sheer numbers and firepower alone cannot guarantee success.

It takes only one determined man with a shoulder-launched groundto-ground missile to halt a tank and, in the present circumstances, force the withdrawal of a whole squadron whose orders are not to fire into civilian areas.

It is, in the words of a Black Watch major: "Like fighting with one hand tied behind your back." Ultimately, the allied plan is to enter Basra in force, but the example of Zubayr, Basra's neighbour, may set the pattern for the near future. British forces took Zubayr town relatively quickly, but sniping and persistent hit-and-run attacks forced a general withdrawal. It is within the 7th Armoured Brigade's control in a loose sense, but it is by no means secure.

The Fedayeen fighters are believed to be under orders from Saddam Hussein's Ba'ath party officials, his favoured henchmen who have everything to lose if he is forced from power.

Air strikes have destroyed three Ba'ath party buildings in Basra in the past four days, but the party officials are still believed to be active. Some have toured the surrounding rural areas terrorising farmers and warning them they and their families will be killed if they co-operate with the allies.

The unseen nature of the enemy is a disquieting factor and among some middle-ranking officers there is dismay over the way refugees are being allowed to leave Basra.

Among thousands who have so far streamed out of the city, a number of young and middleaged men have been identified. While they are searched for weapons at a British checkpoint on a canal crossing known as Bridge Four, there is no way of knowing who they are.

An armoured unit captain, whose men were holding a Fedayeen suspect, said: "It would make more sense to detain everyone in a safe area until we know exactly who they are.

"At the moment we could be letting some very dangerous people slip back into our lines."

But allied commanders are determined to treat refugees and other displaced people with as much kindness as possible.

They have been distributing water and emergency ration packs to the most needy and a British ship carrying food, water and blankets was expected to dock in the port of Umm Qasr today after a delay caused by mine-clearing operations.