Although a previously unheard of group claimed responsibility for the bombing of UN headquarters in Iraq, the US believes it is an "inside job". Michael Jansen reports from Baghdad The US team probing the devastating 19 August bombing of UN headquarters at the Canal Hotel in Baghdad began by interrogating Iraqis guarding the compound. Since some of the guards retained by the UN almost certainly worked as intelligence agents for the ousted regime during the period the hotel was the base for UN weapons inspectors, the investigators were looking into the possibility that one or more of the guards could have helped supporters of former President Saddam Hussein to mount the operation. The focus on "loyalists" rather than other possibilities seemed to indicate that the US team did not take seriously the claim of responsibility by the previously unknown "Armed Vanguards of Mohamed's Second Army", a name suggesting an Islamist rather than a secular Ba'thist background. The notion that the bombing of the Canal Hotel was an "inside job" was based on the fact that the device exploded beneath the office of the UN's chief representative Sergio Vieira de Mello, who was killed along with more than 20 other staff members. However, it is just as likely that the bombers simply chose the only route open to the flatbed lorry which delivered the crude device made of a Russian bomb wired to explosives: the paved roadway into the parking lot alongside the UN compound wall. So far, none of the strikes on foreign troops and military facilities and sabotage operations against infrastructure have involved sophisticated intelligence, great military expertise or equipment beyond that available from Iraq's looted army stores. It would seem that this is true, also, of the 7 August hit on the Jordanian Embassy in Baghdad as well as the UN bombing. This means that almost any of the resistance groups now operating in Iraq could have carried out the operation. Since armed resistance began at the time of the regime's collapse in early April, some three dozen groups have either claimed responsibility for attacks on the occupying forces and other targets or issued communiqués declaring their determination to take up arms against the occupation. There are at least a dozen loyalist formations, including units drawn from Fedda'yeen Saddam (Saddam's Fighters), the paramilitary force set up after the 1991 War. Fedda'yeen units fought well in Iraq's southern cities during the Anglo-American invasion and are thought to have regrouped. Former President Saddam himself, reportedly, established two groups after the Anglo-American attack on Iraq at the end of 1998. The first, Al-Ansar (The Supporters), is said to be an underground formation of highly motivated Ba'th Party militants while the Mujahedin (Holy Warriors) consists of non-Ba'thist Iraqi and Islamist veterans of the wars in Afghanistan, Chechnya and the Balkans. Al-Quds Brigades was established after the Palestinian Intifada erupted at the end of September 2000. Its commander, General Subhi Kamal Erzeyek, was arrested by US troops on 20 August. The National Front for the Liberation of Iraq was formed during the war by secular and religious members of the Republican Guard. Al-Awdah (The Return) made up of ex-members of the security apparatus and disbanded soldiers, has well-organised cells in cities with substantial Sunni Muslim populations like Baghdad, Ramadi and Mosul. A faction calling itself Liberating Iraq's Army has warned the UN and the international community against sending peace-keepers to Iraq. The Organisation of the Jihad Brigades in Iraq targets collaborators. Other groups in this category are New Return, the Political Media Organ of the Ba'th Party, the Popular Resistance for the Liberation of Iraq and the Snake's Head Movement. Sunni Islamist movements, often with tribal connections, have also developed the capacity to carry out guerrilla attacks and sabotage operations. The purely domestic Islamic Movement in Iraq, has a military wing called Al-Farouk Brigades. The Martyr Khattab Brigade is the armed wing of a non-Iraqi Sunni Islamist organisation called the Mujahedin of the Victorious Sect. The Mujahedin Battalions of the Salafi Group of Iraq has as its spiritual mentor, Sheikh Abdullah Azzam, who fought with the Saudi Islamist and founder of Al-Qa'eda Osama Bin Laden against Soviet forces occupying Afghanistan and was assasinated in 1989. Other factions are Muslim Youths, the Islamic Armed Group and Ansar Al-Islam (both of which claim ties with Al-Qa'eda), and the Islamic Liberation Party. Wakefulness and Holy War and the Islamic Armed Group of Al-Qa'eda are both based in the restive city of Fallouja west of Baghdad. The Black Banner organisation, which has both nationalist and religious leanings, calls for attacks on oil installations to prevent Iraq's key natural resource from being taken over by the US. Other anti-Saddam factions which claim to be involved in resistance activities include the Unification Front for the Liberation of Iraq, the leftist General-Secretariat for the Liberation of Democratic Iraq, Al-Anbar Armed Brigades of Iraq's Revolutionaries and the old- fashioned pan-Arab nationalists. Finally, there are informal groupings of regime loyalists and former soldiers who are ready to resist because they believe they have no future under the occupation, and nationalist and patriotic Iraqis who do not want Saddam Hussein to return but are angered by the US failure to restore security and essential utilities and services. In addition to resistance groupings, there are also looters, criminal networks, and gangs of smugglers who use violent means to prevent the reimposition of law and order. A power struggle amongst Shi'ite clerics has also led to killings and bomb attacks like that of 24 August on Ayatollah Mohamed Said Al-Hakim, uncle of the head of the Iran-backed Supreme Council for the Islamic Revolution in Iraq Ayatollah Mohamed Baqer Al-Hakim. The main cause of the emergence of so many resistance factions is US mishandling of the post-war political and economic situation. The US has alienated Iraq's influential Sunni Arabs by favouring the Shi'ite majority and the Kurds. The disbandment of the Iraqi armed forces and dismissal of thousands of civil servants with Ba'thist connections has created a large pool of recruits. And the US failure to provide security and essential services to the Iraqis has made many feel that Washington is interested only in oil. The multiplicity and diversity of anti-occupation factions makes it all the more difficult for the US occupation authority to pin down responsibility for specific operations and to take action against perpetrators. Unless ordinary Iraqis are persuaded that the resistance groups are acting against the country's interests and provide information on their members, it is unlikely that the occupying powers will be able to operate effectively against these groups, particularly since new factions appear to be emerging all the time.