Al Qaida bomb-makers set up two powerful cells in Baghdad

Al Qaida bombmakers have established at least two cells in Baghdad with the capacity to carry out large-scale operations, designed to destabilise American-backed efforts to restore order, say officials of Iraq's new government.

Bernard Kerik, the former New York police chief brought in to the Iraqi police, said the FBI would send experts to Baghdad to lead the investigation into suspected links between Al Qaida and last week's deadly bombing outside the Jordanian Embassy.

Yesterday, Jordanian and U.S. officials identified the fugitive terrorist Abu Musab Al Zarqawi, who was at the centre of pre-war American efforts to establish a link between Saddam Hussain and Al Qaida, as the chief suspect in the embassy bombing.

The device used in the truck bomb was far more sophisticated than anything coalition forces have encountered so far. A mixture of high explosives and TNT, it was triggered by remote control and, according to one security official, may have been assembled abroad before being brought to Baghdad.

"The style of the attack and the explosives used point towards Ansar Al Islam and in particular to Zarqawi, who is still on the run in Iraq," a senior Jordanian official said.

Ansar Al Islam has regrouped after its caves and mountain bases were bombed in the early stages of the war. Its members fled into Iran, where they were given official protection by the Iranian security services, before filtering back into Iraq in the chaotic weeks after the fall of Saddam Hussain.

Al Qaida operatives are also believed to have proliferated in Iraq over the past three months, crossing the borders from neighbouring countries to resist what their leadership describe as the occupation.

Iyad Alawi, the head of the Governing Council's security committee, told The Sunday Telegraph: "Al Qaida are coming in from various places. Some are new, but we have also found traces of sleeper cells. People have reported on their activities in several areas. We certainly know that top Al Qaida bomb-makers and organisers are in Iraq."

The re-emergence of Al Qaida as a clear threat to the coalition forces in Iraq has shaken the confidence of American forces in Iraq.

At a cordon line outside the devastated embassy last week, Staff Sgt Chris Lynch looked pensive as he confirmed the first reports of Al Qaida involvement. "We know who done it all right," he said, "but we aren't going to catch them, that's for sure."

The embassy blast, which came as the Americans marked the 100th day since President George W Bush announced the end of major hostilities, dealt a severe blow to hopes that the wave of post-war violence would soon subside.

The Americans adopted a new, "softly softly" approach to policing in Iraq last week, cutting the number of raids carried out on Iraqi homes across most of the country, including the Sunni triangle – the 200-mile zone that Saddam is crisscrossing to elude capture.