At least 12 people were arrested Friday in connection with the train bombings in Madrid.

The Interior Ministry said six Moroccans, three Syrians, one Egyptian, one Palestinian and one Algerian were arrested in raids in and around the city.

Four of the Moroccans are brothers linked to another Moroccan, Youssef Belhadj, suspected of being the Al Qaeda (search) figure in whose name the attacks were claimed. Belhadj was extradited Friday from Belgium to Spain.

A police spokesman said the brothers, whose family name is Haddad, put Belhadj up in Madrid during a visit in 2003.

The spokesman said the 12 were suspected of being involved in preparations for the attacks, rather than in carrying out the bombings.

Among the detained is 33-year-old Mahamad Tiazounie, of Syrian origin, who is considered the personal assistant of a Tunisian named Serhane Ben Abdelmajid Fakhet, one of seven key suspects who killed themselves in a suicide blast on April 3 as police moved in to arrest them.

About 150 police agents took part in the raids. Police said there could be more arrests.

More than twenty people, most of them Moroccan, have been jailed on provisional charges in connection with the Madrid bombings (search). More than 50 others are considered suspects but are not detained.

The March 11, 2004, bombings on four commuter trains killed 191 people and wounded more than 1,500.