Pinning down al-Qaeda's loose alliance

Many bodies have still not been identified

Suspicion of who was behind Saturday's bomb that killed at least 188 people in Bali has centred on militant Islamic groups in Indonesia believed to have links with al-Qaeda.

With no claim of responsibility and no evidence to point to any one group, the speculation is mounting that, like a number of attacks since 11 September 2001, this is the work of a group loosely allied to Osama Bin Laden's organisation.

The BBC's security correspondent, Frank Gardner, says that al-Qaeda has fragmented and there is no central direction of its affiliated groups.

Instead, he says, various Islamic militant organisations across the world carry out attacks on targets but without being directed to do so by al-Qaeda.

There have been at least 12 other attacks in which Islamic militants sympathetic to al-Qaeda might have been involved.

• 22 December 2001 - British Muslim convert Richard Reid attempts to blow up an American Airlines plane with a bomb in his shoe.
• 22 January 2002 - Gunmen attack the US Centre in Calcutta, killing four Indian policemen.
• 23 January 2002 - US journalist Daniel Pearl seized and later killed in Karachi, Pakistan.
• 17 March 2002 - Grenades used to kill five people in an attack on a Christian church in Islamabad, Pakistan.
• 11 April 2002 - A bomb in a lorry kills 19 people outside a synagogue in Tunisia.
• 8 May 2002 - Suicide bomb attack in Karachi kills 14.
• Car bomb attack on US consulate in Karachi kills 12 Pakistanis.
• 6 August 2002 - Six Pakistani Christians killed in attack by gunmen on a church in Muree, Pakistan.
• 25 August - Bomb blast near UN residences in Kabul injures two
• 6 October 2002 - One sailor killed in explosion on French tanker off Yemen coast.
• 8 October 2002 - Two gunmen kill a US marine taking part in a military exercise in Kuwait.
• 14 October 2002 - shots fired at US troops engaged in military exercise in Kuwait

Links with Bin Laden

Many of the Islamic groups believed to have been involved in the series of attacks on Western or Western-linked targets have a history of contacts with al-Qaeda.

In the case of the Bali attack, most suspicion has fallen on a regional group called Jemaah Islamiah, which supports the formation of a south-east Asian Islamic state, according to the BBC's security correspondent, Frank Gardner.

The leader of Jemaah Islamiah denied that he had had any role in the bombing.

It was the world's worst terror attack since 11 September last year

"All the allegations against me are groundless. I challenge them to prove anything," Abu Bakar Bashir told AP by phone from Solo, in central Java, where he runs an Islamic school.

"I suspect that the bombing was engineered by the United States and its allies to justify allegations that Indonesia is a base for terrorists," he said.

The US has accused Jemaah Islamiah, which seeks to establish a pan-Islamic state in South-east Asia, of plotting bomb attacks against the US, British and Australian embassies in Singapore last year. Indonesia has ignored US calls to arrest Mr Bashir.

Indonesian investigators probing Saturday's bomb attack on the island of Bali say they have the names of several suspects and the defence minister has blamed al-Qaeda.

Devolving responsibility

A major problem in pinning down responsibility for attacks that seem to be the hallmark of al-Qaeda is the loose and often indefinable links between it and other militant Islamic groups.

An Australian terrorism expert, Clive Williams, told the British Daily Telegraph newspaper that al-Qaeda might be indirectly involved in attacks like the Bali one as its affiliated groups frequently act with a degree of autonomy.

Yemen now believes the Limburg explosion was "terrorism"

The Guardian newspaper's security analyst, Richard Norton-Taylor, warns that attributing responsibility is difficult as al-Qaeda "is not a traditional terrorist organisation with a disciplined hierarchy".

Instead, he says, "it is more like a movement, almost amoeba-like, with varying degrees of support and contacts with other groups throughout much of the Muslim world".

In countries like Indonesia, with its own Christian-Muslim and ethnic conflicts, groups sympathetic to al-Qaeda may well be following their own agendas.

But because of their common Islamic and anti-Western background the results can be the same for Western security.