Germans hunt for bomb plot network

German police launched an intensive search yesterday for suspects believed to have supported three al-Qa'ida-linked Islamic militants arrested for planning potentially devastating bomb attacks on Frankfurt's international airport and the United States Air Force base at nearby Ramstein.

A government spokesman said police were hunting a group of seven militants who acted as the back-up group for the two German Islamic converts and a Turkish citizen arrested on Tuesday for plotting what were described as "massive" and "imminent" bomb attacks.

The three were arrested at a rented holiday apartment near the central German town of Kassel with chemicals and bomb-making equipment capable of producing explosions bigger than those detonated in the Madrid and London bombings of 2004 and 2005.

August Hanning, a senior Interior Ministry official, said yesterday that the three, all members of an al-Qa'ida-linked group called the Islamic "Jihad Union", had been actively supported by a splintered cell comprised of other Germans converts and Turkish citizens."This is the network we are aware of at the moment," the official added.

German intelligence sources partly identified three suspects in that network – a 22-year-old Turkish citizen referred to as Zafer S, who is suspected of having recently left Germany for Turkey; Tolga D, a German Islamic convert, and a Lebanese citizen who was referred to as Hussein al-M. They said three others were Turkish citizens whose names were known to police but no details were given about the seventh suspect.

The arrests on Tuesday, which appeared to have forestalled potentially the most serious and devastating terrorist attack in Germany, reignited political controversy over demands for tougher security measures, including police powers to conduct clandestine online surveillance and the monitoring of converts to Islam.

Wolfgang Schäuble, Germany's conservative Interior Minister, renewed a controversial demand that police be equipped with special powers to monitor individuals' internet activities. "The terrorists are increasingly linked up through the internet, in closely defined and exceptional cases, there has to be the possibility to secretly spy on computers," he said.

But Mr Schäuble's Social Democrat coalition partners in government have rejected the idea.

It was the fact that two of the arrested suspects were Germans who had recently converted to Islam that caused the most concern yesterday.

Police experts said only 70 Islamic converts from Germany's 3.3 million-strong Muslim community actually posed a threat to security but Günther Beckstein, Bavaria's outspoken right-wing Interior Minister demanded that police and the intelligence services should monitor individuals who had recently converted. He added: "Converts have a strong tendency towards fanaticism which they develop to try to prove that they are worthy of their new religion," he insisted.

Figures published yesterday by Germany's Islamic Archive showed that the number of Germans converting to Islam increased dramatically last year with 4,000 having embraced the faith in 2006 compared to only 1,000 in 2005.