The prime suspects in the failed attempt to blow up two German trains were partially motivated by anger over the recent publication of Prophet Muhammad cartoons, a leading investigator said in an interview released Saturday.

The Danish newspaper Jyllands-Posten first published the 12 cartoons in September 2005, including one showing Muhammad wearing a turban shaped like a bomb.

Some of the caricatures were republished in German newspapers and other European media months later, sparking protests across the Muslim world, where many considered the cartoons a violation of traditions prohibiting images of their prophet.

FOX CountryWatch: Germany

Jihad Hamad told Lebanese interrogators that fellow suspect Youssef Mohamad el Hajdib considered the publications "an attack of the Western world on Islam," Joerg Ziercke, head of Germany's Federal Crime Office, told Focus magazine in an interview released to The Associated Press ahead of publication.

Meanwhile, Lebanese prosecutor Pierre Francis on Saturday charged Hamad, el Hajdib and four others with attempting to kill a large number of people, court officials said. Two of the men are being held in Germany and were charged in absentia, officials said.

The move appeared to signal that Beirut would refuse to extradite to Germany the four men held in Lebanon.

The men are suspected of planting crude bombs July 31 on two trains at Cologne station, where authorities said they were seen in grainy surveillance camera video pulling wheeled suitcases. The bombs were found later in the day on regional trains in Koblenz and Dortmund. Authorities have said that the detonators went off but failed to ignite the devices.

Ziercke told Focus magazine that the suspects also were motivated by the killing of al-Qaida in Iraq leader Abu Musab al-Zarqawi on June 7 in a U.S. airstrike north of Baghdad.

"Both of the prime suspects believed that international terrorism had lost its most important leader," Ziercke said. "The conflict in Lebanon also played a role (in motivating them) though we know the planning for the attacks had already begun earlier than that." Fighting between Israel and the Islamic militant group Hezbollah broke out July 12.

Germany's Federal Crime Office, or BKA, confirmed the content of the interview.

El Hajdib, 21, was arrested Aug. 19 in the northern German city of Kiel, and Hamad, 20, was picked up a few days later in Lebanon. In addition to Hamad, Lebanese authorities have arrested three other men in connection with the case: Ayman Hawa, Khaled Khair-Eddin el-Hajdib, Khalil al-Boubou.

German officials also have taken a 23-year-old Syrian, Fadi al-Saleh, into custody in the southern city of Konstanz on suspicion he did Internet research in preparing the bombings.

Ziercke told Focus magazine he did not believe Hamad and el-Hajdib came to Germany with the intent to prepare attacks.

"The radicalization first took place here, through al-Qaida propaganda found on the Internet," he said.

The bomb plans were found on the Internet, and the devices would have cost a total of about $250 to $385 to build, he said.

But Ziercke rejected suggestions that the sloppy construction of the bombs and other points spoke to the work of untrained amateurs.

"The details that the suspects allowed themselves to be filmed, left DNA traces and fingerprints behind and traveled with their normal passports is not compelling evidence they were amateurs," he said.

"To the contrary: They had counted on their plan working. Then the crucial clues would have been obliterated. We, for example, would never have found any suitcases that we could match to people seen on video surveillance."

FOX CountryWatch: Germany