An imam and five other men have been arrested in a series of anti-terror raids in Italy.
The suspects are accused of helping an Algerian militant group
Police say they are investigating possible links with Osama Bin Laden and the al-Qaeda terror network.
The raids were launched at dawn on 40 sites, including a mosque, in and around the northern city of Milan.
The detained imam was named as as Moroccan Mohamed el Mahfoudi, 38, of Gallarate mosque on the outskirts of the city.
Five Tunisians were also held.
The raids were "were part of a major operation against international terrorism" co-ordinated by Milan prosecutor Luigi Orsi, said a police statement.
The suspects are accused of providing financial and logistical support to a militant Algerian group, the Salafist Group for Preaching and Combat (GSPC).
The raids were staged in and around Milan
A judicial source said a seventh suspect was still being sought.
The charges against them are said to include abetting and financing a terrorist organisation, false accounting, involvement in illegal immigration, receiving counterfeit documents and trafficking in stolen cars.
A police source said the men were not themselves suspected of carrying out terror attacks.
But police are investigating whether they were running businesses and other activities as "fronts" to raise money for the militants.
Bank accounts in at least 16 countries in Europe, the Middle East and North America are thought to be under scrutiny, as police probe what they believe is a complex web of financial dealing.
Possible ties to key 11 September suspect Ramzi Binalshibh are also being examined.
A Tunisian man was jailed in Milan last year for criminal association aimed at producing counterfeit documents and involvement in illegal immigration to Italy.
At the time of his arrest in April 2001, the man, 34-year-old Essid Sami bin Khemais, was thought by judges to be linked to Osama Bin Laden's al-Qaeda network, although terror charges against him were not pursued.
About 170 Italian officers took part in the Milan raids, led by financial police.