A 27-year-old German man was arrested Thursday by a police special-ops team in the western city of Bochum on charges he was part of an al-Qaida bomb plot in Europe, the federal prosecutors' office said.
Suspect Halil S. is accused of being part of the so-called "Duesseldorf Cell." The group was allegedly plotting the bombing before its three main members were swept up by police in April, prosecutors' spokesman Marcus Koehler said.
At the time of their arrest, authorities said the three were working on making a shrapnel-laden bomb to attack a crowded place inside Germany, such as a bus, and were experimenting with explosives and detonators but had not chosen a specific target.
Halil S., whose last name was not provided in accordance with German privacy laws, is accused of supporting the three with financial and logistical help, and then attempting to carry forward their plot after their arrest, Koehler said.
"The accused is strongly suspected to have followed up on the attack plans despite the arrest of the other members of the co-called Duesseldorf Cell," Koehler said.
The search of his apartment, however, turned up no weapons, no explosives and no evidence of any concrete attack plans, according to a security official speaking on condition of anonymity because the investigation is ongoing.
Prosecutors say the main suspect in the case, 30-year-old Moroccan Abdeladim El-Kebir, left Germany in early 2010 and trained in an al-Qaida camp in the Waziristan region in Pakistan along the Afghan border.
He returned last year to carry out the attack after contact with high-ranking al-Qaida member Younis al-Mauritani, who was apprehended earlier this year by Pakistani agents working with the CIA.
A written exchange with al-Mauritani that was found at El-Kebir's home indicated he belonged to a group that American security officials last year warned may be plotting attacks in Europe, a German official told the AP in May.
The German official suggested that the letter contained some indication that Osama bin Laden had been kept abreast of the plot to attack Europe. The German official spoke on condition of anonymity because of the sensitivity of the information.
By summer 2010 El-Kebir had returned to Germany and joined up with Jamil S., a 31-year-old German-Moroccan citizen, and Amid C., a 19-year-old German-Iranian, and the group began "concrete attack plans" by December of that year, Koehler said.
Halil S. was recruited by El-Kebir by April 2011 to provide financial and logistical help _ raising money and also procuring false papers, Koehler said.
Authorities had the group under observation and the three main suspects were arrested at the end of April when investigators learned they were trying to obtain a detonator for a bomb, Koehler said.
Authorities conducted a series of other raids linked to the probe Thursday, with 150 police officers searching apartments of five other suspects in the states of North-Rhine-Westphalia, Schleswig-Holstein and Hamburg, as well as 11 other homes and two shops.
Another suspect, identified only as Florian M., was arrested in Kiel on charges of involvement with Halil S.'s criminal activities to make money, but is not thought to have known of the attack plans.