Sept. 5 (Bloomberg) -- Police arrested three men suspected of planning ``massive'' terrorist attacks on U.S. and other targets in Germany, preventing the deaths of ``many, many people,'' Chief Federal Prosecutor Monika Harms said.

Two Germans and a Turkish national were detained yesterday at a house in Oberschledorn, a village in the western German state of North Rhine-Westphalia, officials said. Bomb-making materials and military detonators were also seized. The trio are alleged members of a local cell of the Islamist terrorist organization Jihad Union, which has links to al-Qaeda, Harms told reporters in Karlsruhe today.

Police foiled ``one of the worst terror acts ever planned in Germany,'' Harms said. ``We've said repeatedly for months that Germany is in the sights of Islamist terrorism and that we have to be vigilant.''

The men were planning attacks on sites in Germany used by U.S. citizens, including discos, bars and transport sites, Harms said. The hydrogen peroxide-based liquid explosives seized were equivalent to 550 kilograms of TNT -- greater explosive power than in the Madrid bombings of March 2004 or the London bombings of July 2005, Joerg Ziercke, head of the Federal Criminal Office, told the news conference.

``The main motivation of the group in Germany was hatred of American citizens,'' Ziercke said. While no specific targets had yet been selected, one possible scenario involved simultaneous car bombs placed at locations throughout the country. The aim was probably to have been ``a high number of victims'' given the amount of explosives involved, he said.

Elite GSG9 Unit

The alleged bombers, aged between 22 and 28, lived in the western states of Baden-Wuerttemberg, Hesse and Saarland. They were detained by the elite GSG9 anti-terrorist unit when they started to prepare the hydrogen peroxide and were about to change location, Zierke said. Gunshots were fired when one suspect tried to escape, slightly injuring a police officer, he said. The authorities had already secretly swapped the 12 barrels of hydrogen peroxide for liquid of a lower explosive concentration, Ziercke said.

Chancellor Angela Merkel praised the ``great success'' of the federal and regional authorities in tracking the suspects over months to avert a ``terrible'' attack, the consequences of which may have been ``indescribable.''

``When it comes to fighting terror, international cooperation is of crucial importance,'' Merkel told reporters in Berlin. ``The lesson from this is the danger is not just abstract, it's real.''

Bush's Comment

President George W. Bush was briefed on the arrests in Sydney, Australia, where he is attending an economic summit of Asian-Pacific nations.

Bush was pleased by the work of the German authorities and the arrests ``remind us of the threat that terrorists pose around the world and the need to continue to pursue them wherever they are,'' said Gordon Johndroe, a spokesman for the White House National Security Council.

Police, who were already watching individual members of the group, stepped up their operations in February this year after they were discovered to be observing the U.S. army barracks at Hanau, outside Frankfurt, Ziercke said. The police operation, involving 300 officers across the country on the case every day over the past six months, became the biggest handled by the Federal Criminal Office.

The Turk, a Muslim, and the two Germans, both of whom were converts to Islam, represented the ``core'' of a group that includes further suspects, Ziercke said. The three may have trained in Pakistan to carry out attacks in Germany, he said.

New Technology

Police are studying computers and other material seized in raids carried out on 41 sites in six western German states made after the arrests, Zierke said, adding that the trio had used sophisticated new Internet technology to communicate.

The upcoming anniversary of the Sept. 11 attacks on the U.S. may have been ``a certain motivation boost,'' according to Federal Prosecutor Rainer Griesbaum. One of those arrested is considered the head of the group, he said.

Germany faces a higher threat from terrorism because of its military involvement in Afghanistan, the government said in June. Germany has deployed more than 3,000 soldiers in Afghanistan as part of North Atlantic Treaty Organization efforts to combat Taliban insurgents.

German media reports said the men planned to attack Frankfurt airport, Europe's third busiest after London Heathrow and Paris Charles de Gaulle, and a U.S. military base in Ramstein, about 80 kilometers (50 miles) southwest of Frankfurt.

Ramstein Base

The Ramstein base serves as headquarters for the U.S. Air Forces in Europe and is also a NATO installation.

``The security status of our bases in Germany remains the same as yesterday, that is unchanged `Bravo','' Lt. Cmdr. Corey Barker, press spokesman for United States European Command in Stuttgart, said in an interview. ``We have no confirmation from the German authorities that Ramstein was actually targeted.''

The U.S. operates a four-tier alert system, from Alpha to Delta, Barker said. Bravo is defined as an ``increased and more predictable threat of terror activity,'' he said.

Police in Denmark arrested eight ``militant Islamists'' alleged to have al-Qaeda connections and who were suspected of plotting a ``major'' attack, the country's intelligence service said yesterday.

Ziercke said that while the structure of the German group was similar to that uncovered in Denmark, ``no direct links'' have been established.

To contact the reporters on this story: Claudia Rach in Berlin at crach1@bloomberg.net; Brian Parkin in Berlin at bparkin@bloomberg.net.

Last Updated: September 5, 2007 21:41 EDT