Al-Qa'ida suspects held in five nations

Men questioned in Britain, Kenya, Germany, Italy and Turkey as UK warns against travel to Saudi Arabia

A key figure linked to the suicide bombing of an Istanbul synagogue was captured while trying to slip into Iran with a fake passport and charged with treason, according to reports last night.

The suspect, whose name was not released, allegedly plotted and approved the 15 November suicide truck bombing of the Beth Israel synagogue - one of four attacks during the course of the week, which killed 61 people, Istanbul's Deputy Police Chief Halil Yilmaz said.

The seizure follows the arrest of more than two dozen al-Qa'ida suspects, including some on the FBI most wanted list, in Kenya. The suspects are accused of taking part in the 1998 car bombing of the US Embassy in Nairobi and the November 2002 attack on a coastal hotel in Mombasa, according to Christopher Murungaru, Kenya's National Security Minister.

Meanwhile, the British embassy in Saudi Arabia warned that "terrorists may be in the final phases of planning attacks" in the Gulf state. The warning came four days after Saudi officials said they thwarted a planned strike by militants who had packed a car with more than a ton of explosives.

It served to remind some 30,000 Britons in Saudi that they are still at risk of attacks from Osama bin Laden's al-Qa'ida network.

There have also been anti-terrorism arrests in Italy and Germany. Italian police said on Friday they had smashed a network suspected of recruiting suicide bombers. German officers were understood to be questioning a suspected Algerian extremist who was arrested in the port of Hamburg on Friday at the request of Italian authorities.

The detention of the suspect in Turkey is the first major arrest in the investigation into the four suicide truck bombings that devastated two synagogues on 15 November and the British Consulate and a British bank five days later.

Twenty-nine people, including the two bombers, perished in the synagogue bombings. The attacks on the British targets claimed 32 lives, including the two bombers. All four suicide bombers were Turks.

Police had been tipped off that the man planned to flee Turkey using false documents, Mr Yilmaz said.

They brought the man - bearded and apparently in his 20s - to the wrecked Beth Israel synagogue earlier yesterday where he was seen describing the attack to an investigator, occasionally turning to point at a street or the synagogue. He was handcuffed and dressed in a navy blue police flak jacket.

Turkish police routinely take suspects to the scene of a crime to describe how it was carried out. He was brought to the scene in an armoured police car and was surrounded by police officers.

It was not clear why the suspect tried to flee to Iran. Turkish authorities have in the past accused Iran of backing radical Islamic groups in Turkey and alleged that members of an Islamic group suspected in a series of killings had trained in Iran and received support from the government.

American counter-terrorism officials said last month that a few senior al-Qa'ida operatives who fled to Iran after the Afghan war may have developed a working relationship with a secretive military unit linked to Iran's religious hard-liners.

Iran has said it has some al-Qa'ida operatives in custody but has refused to identify them or to say how many.

Some circles in Washington have suggested that they could include al-Qa'ida agents wanted in connection with the 1998 bombings of US embassies in Kenya and Tanzania or with May's bombings of foreign compounds in the Saudi capital, Riyadh.