"The kingdom not only denounced the September 11 attacks but displayed willingness to fight against terrorism and continues to cooperate with international efforts in this respect, particularly US efforts," a senior Saudi official told AFP.

The official who asked not to be named, carefully avoided whipping up the fierce storm that followed the suicide hijackings, when the US media led allegations that the conservative Muslim kingdom bore core responsibility.

The fact that 15 of the 19 suicide hijackers had Saudi nationality and the mastermind Osama bin Laden is a scion of a leading Saudi family with close ties to the royal rulers proved difficult for the Riyadh government to swallow.

Accusations still surface today of being soft on terror and of allowing extremist Islamist elements to flourish and find finance, despite suicide bombings in the capital on May 12 which killed 35 people.

"Saudi Arabia is itself a target of terrorist acts," pleaded the official, recalling the attacks on expatriate housing compounds attributed to bin Laden's al-Qaeda network.

The bloodshed in Riyadh shocked and galvanised the authorities to hunt down the killers. Shootouts between wanted gunmen and security services became common and several al-Qaeda leaders were shot dead, captured or surrendered. Scores more suspects have been detained.

The shootouts offered physical proof of the Saudi authorities' determination to crack down on the terrorists who roamed the kingdom, finding succour among a network of supporters and sympathisers.

Stricter controls of the sometimes shadowy agencies suspected of channeling charity money to Islamic extremists have also been put in place.

The interior ministry this week went as far as to urge all parents to report their missing sons to the security services for fear that they may have joined terror groups.

The interior ministry published the appeal in the press along with a free 990 telephone service, breaking another subject once considered taboo.

Numerous young Saudis have disappeared in recent years to join various Islamist causes from Afghanistan to Chechnya, although many also go to tourist hotspots in Asia without informing their conservative Islamic families.

Around the September 11 anniversary, Saudi intellectuals have stressed the need to acquit Islam of any extremist tendencies and to make a clear distinction between one of the world's great monotheistic religions and the radical groups that have attempted to hijack it.

Author Hani Wafa pondered the woes September 11 had caused the Saudis in general and Moslems in particular.