Federico Gambarini / EPA

The accused Abdeladim El-K and Amid C. shake hands and smile in a court room in Duesseldorf, Germany, on July 25, 2012. The trial of four suspected al-Qaida terrorists started under most stringent safety precautions. They are accused of planning a terror attack in Germany. The image was sent to NBC News already blurred by EPA.

Four men accused of membership in an al-Qaida cell and charged with plotting an attack in Germany went on trial in the western city of Düsseldorf on Wednesday.

Prosecutors said the men, ages between 20 and 30, had intended to stage a "sensational terror attack," but had not decided on a specific target. The men were arrested in April of last year.

A Moroccan named as Abdeladim El-K. was the ring leader, according to prosecutors, and had trained at an al-Qaida camp in the Waziristan region of Pakistan in 2010.

He learned how to use firearms and make bombs and was ordered to build up a network for organizing attacks in Germany.

Under the German legal system, the men will not be asked to formally plead guilty or not guilty, but will have a chance to speak during the trial.

Militant Islamists have cited Germany's military presence in Afghanistan as grounds for attacking the country.

Abdeladim El-K. recruited three men he knew from his student days, a German-Moroccan named as Jamil S., a German-Iranian named as Amid C. and German citizen Halil S, prosecutors said.

He gathered information on the security set-up at public buildings, airports and stations, they added.

Jamil S. worked on producing explosives while Amid C. and Halil S. dealt with communications with the al-Qaida leadership, prosecutors said.

Rolf Tophoven, director of the Essen Institute for Terrorism Research, told Deutsche Welle the suspects were dangerous because they had access to al-Qaida's structure.

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"What was special about the Düsseldorf Cell is that they had direct contacts to the Pakistani-Afghan border area," he said. "That meant they had access to the al-Qaida structure - to the core of al-Qaida."  

According to Deutsche Welle, this is the first group in Germany to have an alleged connection to al-Qaida.

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Investigators wire-tapped the computers of the alleged terrorists and intercepted their e-mails, Deutsche Welle reported. They also listened in on conversations in the men's Düsseldorf apartment over several weeks.

The group did not discuss a specific target, but authorities intervened when the men allegedly said they wanted to "slaughter the dogs."

The trial is expected to run until November.

Reuters contributed to this report.

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