A clerical worker was named yesterday as Germany's first suicide bomber and blamed for the deaths of two American soldiers in Afghanistan.

Cueneyt Ciftci, 28, who was born in Bavaria to a family of Turkish immigrants, is believed to have driven a pick-up truck laden with explosives into a US guard post on March 3.

An Uzbek terror group, the Islamic Jihadist Union (IJU), claimed responsibility. In the chaotic aftermath of the explosion, insurgents raked the Americans with gunfire and killed 60 men, the group claimed, adding that: “He was a brave Turk who came from Germany and exchanged his life of luxury for paradise.”

The US denied the hugely inflated casualty figure. For a week or so both the Germans and the Americans discounted the claims that the bomber was Ciftci.

But then a video clip of the Bavarian, clearly recognisable to his neighbours, turned up. It showed the bearded, smiling man brandishing a pistol and pointing one finger as if to Heaven. German police are tracing his position in a network that seems to lead back to radical Bavarian mosques and to a group arrested last September for preparing explosives to bomb Frankfurt airport.

Ciftci's involvement puts further pressure on Angela Merkel, the Chancellor, to shift forces from the relatively calm north of Afghanistan to the more active south.

Yesterday a suicide car bomber there killed three Nato soldiers, two Danish and one Czech, as well as an interpreter and three civilians. “We have to start looking at what this means for our society,” said a German security official. “How open are we for Islamic radicalisation?”

Ciftci was born in Freising in Bavaria, the son of Turks who had migrated in the 1960s. He did well at school, spoke German with a lilting Bavarian accent. In theory he could have become a German citizen but he chose to remain a Turk. The family moved near Nuremberg, and he started to say his prayers at a mosque that has been under surveillance.

He married and had two children but last April he resigned from his clerical job and deregistered himself at the town hall. Most foreigners do not bother to do this when leaving the country, but Ciftci was a stickler for German bureaucracy.

His exit seems to have been organised by his friend Adem Yilmaz, under arrest after police raids broke up his cell of explosives experts preparing for an attack on Frankfurt airport, Ramstein airbase and other US targets in Germany. The other members of the cell, Fritz Gelowicz and Daniel Schneider, were white native Germans prompting the authorities to worry about German converts to Islam.

But the real cause for concern was Yilmaz - like Ciftci, a Turk with deep roots in Germany, who had, unnoticed by the authorities or the neighbours, turned into an Islamic radical. For decades the German authorities have assumed that the more than two million Turks in the country were essentially politically neutral, apart from a sprinkling of support for the Kurdish Workers' Party.

But the connections between radical clergy - the mosque in Ulm seems to have inspired many radicals, Turks and non-Turks, across Germany - the movement of preachers between Pakistan and Europe and the access to training camps close to the Afghan border have made some German Muslims regular pilgrims.

Yilmaz is said to have organised a network that guided Turks along each stage of the journey to the Pakistan-Afghan border. Police have found e-mails between the IJU in Pakistan and Gelowicz alerting him to the arrival of “two families”. One of the families is presumed to have been that of Cueneyt Ciftci, reporting for action.

Times Recommends

• ‘Thousands of Tamils dying’ in Sri Lanka camp
• Jackson 'rebuilt his nose before he died'
• Tehran: militiamen attack protesters