Bin Laden deputy calls for a repeat of 11 September

With America already jittery over warnings of a possible terror strike in the US, an audio-recording purporting to have been made by Osama bin Laden's deputy was broadcast yesterday, calling on Muslims to repeat the attacks of 11 September.

The tape, said to have been made by Ayman al-Zawahiri, criticised Arab governments for their close ties to Washington and for supporting the war against Iraq. Broadcast by the Arabic language channel al-Jazeera, it said: "Consider your 19 brothers who attacked America in Washington and New York with their planes as an example."

The tape was broadcast as military bases and installations around the US were put on maximum alert after the Defence Intelligence Agency raised its threat level to the highest possible.

The move, which resulted in the deployment of additional anti-aircraft missile systems and increased air patrols in the Washington area, followed the raising of the government's general terror alert on Tuesday to "orange", its second highest level.

Mr Zawahiri, who is on the FBI's most-wanted list and who carries a reward of $25m (£15m), has been on the run since the US-led war in Afghanistan. He is presumed to have escaped with Bin Laden, possibly taking refuge in the border region of Afghanistan and Pakistan. The last statement attributed to him was made in an online militant newsletter in February which called on Muslims to respond to oppression with violence.

In the broadcast, a voice said to sound like that of Mr Zawahiri when compared to previous recordings, said: "Here is Saudi Arabia, where planes are launched from their airports, from its lands.

"Here is Kuwait, where the heavy armies march from its lands. Here is Qatar, where the command of the campaign is based. Here is Bahrain ­ the command of the [US Navy's] Fifth Fleet remains inside it.

"Here is Egypt, the marine ships pass through its canal. Here is Yemen, the crusader ships are provided with fuel. Here is Jordan, where the crusader troops are present and the batteries of the Patriot missiles are erected there to protect Israel."

The call for Muslims to launch attacks similar to those in New York and Washington will add to concern among intelligence officials in Washington that al-Qa'ida could be in the middle of a fresh "operational wave", of which the attacks last week in Saudi Arabia and Morocco were just part.

Vince Cannistrano, a former senior CIA counter-terrorism officer, said the intelligence community believed that while al-Qa'ida might not be capable currently of carrying out the sort of coordinated attack that led to the destruction of the World Trade Centre, it was clearly still capable of launching less complex assaults.

"Very few people think [al-Qa'ida] could do another 9/11-type operation, though no one will say that on the record," he said. "It is carrying out violent attacks when it can do so. It is embedded inside many Islamic countries."

Officials in Saudi Arabia claimed yesterday that three Moroccans arrested this week at Jeddah airport were planning to hijack a civilian airliner and crash it into the National Commercial Bank. A security source said: "There was confusion at passport clearance. The three were behaving suspiciously. When asked if they were travelling together, one said 'no' and one said 'yes'. Then they were arrested."

It is unclear whether the Saudi authorities believe the men are linked to last week's suicide bombings in Riyadh, in which 34 people were killed, or the bomb attacks in the Moroccan city of Casablanca, which killed 41 people.

Al-Qa'ida's call to arms: 'turn the earth under their feet into fire'

Excerpts from the tape believed to be narrated by Ayman al-Zawahiri

"Here is Saudi Arabia, where planes are launched from their airports. Here is Kuwait, where the heavy armies march from its lands. Here is Qatar, where the command of the campaign is based. Here is Bahrain, the command of the Fifth Fleet remains. Here is Egypt, the marine ships pass through its canal. Here is Yemen, the crusader ships are provided with fuel. Here is Jordan, where the crusader troops are present. After that, they shout with hypocrisy and trickery that they are against the war on Iraq.

"Protests, demonstrations, and conferences won't work. Nothing will help you except harming your enemies ­ American and Jews. Oh Muslims, take your decision against the embassies of America, England, Australia and Norway, their companies, and their employees. Turn the earth under their feet into fire.

"Don't allow Americans, Britons, Australians and Norwegians, who are the killers of your brothers in Iraq, to live in your countries.

"Consider your 19 brothers who attacked America with their planes as an example. The mujahedin in Palestine, Afghanistan and Chechnya and also in the heart of America and the West are making those crusaders taste colours of death and the coming days will bring news that will warm your heart, God willing."