As hotel workers mopped blood stains at the five-star hotels targeted by the bombers — believed to have been sent by Abu Musab al-Zarqawi, the leader of Al-Qaeda in Iraq — Jordanian security forces said they had arrested 120 people, mainly Iraqis and Jordanians.

Security sources said they believed the bombers were Iraqi, but that they had received help from Jordanian soldiers who had been seduced by radical preachers secretly aligned with Zarqawi.

“It is true that Amman is swarming with Iraqis and Iraqis don’t need a visa to enter Jordan,” a Jordanian security source said. “But we suspect a triple suicide attack of such magnitude had to have been assisted by inside information.”

Amman is home to about 500,000 Iraqis, ranging from refugees from the regime of Saddam Hussein who never went back to wealthy businessmen who find it a safer place to work than Baghdad.

Iraqis working for Zarqawi, a Jordanian national who has a $25m American bounty on his head, are well financed and find it easy to fit in.

The Jordanians’ fear that Al-Qaeda might have infiltrated the armed forces was raised for the first time in August, when a missile was fired from the shore at an American warship in the Red Sea port of Aqaba.

“They are inside,” a security source said. “It remains to be seen how many they are and how dangerous.”

Al-Qaeda in Iraq appeared unusually anxious to justify the attacks, issuing on Friday the third statement since the bombs exploded at the Grand Hyatt, Radisson SAS and Days Inn hotels.

Earlier statements justified the attacks by saying the hotels were “sewers” for Israeli spies and westerners. The latest praised the bombers as “Iraqis . . . (who) vowed to die and chose the shortest route to receive the blessings of God”.

It said there were four bombers, including a wife who “chose to accompany her husband to martyrdom”. Yesterday, however, Jordanian sources insisted there had been three male suicide bombers and no women.

The Al-Qaeda messages appeared to be an appeal for Arab sympathy. Iraqis are seen in the Middle East as heroic resisters of the American “occupation forces”.

As a Jordanian national, Zarqawi would well know the pulse of Jordan. He was a petty thief jailed for 15 years, but released by King Abdullah in a traditional amnesty given when the king ascended the throne.

Zarqawi left Jordan for Afghanistan but had so little respect for Osama Bin Laden, the Al-Qaeda leader, that he set up his own training camps there. Zarqawi wanted to attack Israel and targets allied to the Jewish homeland, while Bin Laden was focusing on western targets. Only recently did Zarqawi join forces with Bin Laden.

If it was Zarqawi’s idea to try to elicit sympathy for his attacks, it appeared to have failed. Thousands of Jordanians have denounced him as a “traitor”.

Analysts could not remember an incident that had caused such anger and revulsion to be voiced across the Middle East, largely because one of the bombers blew himself up at a wedding reception of 300 guests.

Abdel Bari Atwan, editor of Al Quds Al Arabi, the independent Arabic newspaper, called Zarqawi’s attacks in Amman a “fatal blow to his popularity”.

• Bruce Willis, the American film star, has offered $1m to any civilian who turns in Zarqawi or Bin Laden.

  Additional reporting: Widiane Moussa

Explore World News

• Iraq News

• US & Americas News

• Europe News

• Middle East News

• Asia News

• Africa News

• Ireland News

Times Recommends

• Cheney delivers warning to Moscow
• Le tout Paris asks Dati: 'Who's the daddy?
• Palin lawyers are accused of stalling inquiry