Madrid, Spain ? Three al-Qaida suspects were taken into custody Tuesday, including one who had videotaped several American landmarks including the Golden Gate Bridge, the Sears Tower, the Statue of Liberty and the World Trade Center.

Police said they were convinced the footage, taken during a 1997 visit to the United States by one of the detainees, was much more than “tourist curiosity.”

A California National Guardsman keeps watch at Fort Point below the Golden Gate Bridge in San Francisco. California police on Tuesday doubled security around the Golden Gate Bridge, Disneyland and Universal Studios after potential targets turned up in what are believed to be terrorist videos in Spain.

At least one suspect was recruited by a man whom Spanish authorities say helped prepare the Sept. 11 attacks and was linked to the al-Qaida cell that included hijacker Mohamed Atta.

It was a further indication that Spain, with a growing Arab immigrant population, may have been used by al-Qaida as the setting for crucial logistic support in the Sept. 11 attacks.

Spain has been a focal point of the overseas investigation launched after the terrorist attacks on the United States. An FBI task force is working with law enforcement authorities in Spain to locate and capture suspected terrorists, including men with terrorist links who have traveled to the United States in recent years.

Investigators have already gathered ample evidence that Atta visited Spain twice in 1991, including a weeklong trip in July where he may have attended a series of meetings with other al-Qaida operatives.

In November, authorities arrested Imad Yarkas on charges he led an al-Qaida cell with links to Atta’s cohorts in Hamburg, Germany. Authorities have said they recorded phone conversations in which Yarkas allegedly spoke in code about the suicide attacks.

The men detained Tuesday were Ghasoub Al-Abrash Ghalyoun who shot the videos in the United States as well as Abdalrahman Alarnaot Abu-Aljer and Mohamen Khair Al Saqq. They were all from Syria, although Ghalyoun and Abu-Aljer, detained in Madrid, were naturalized Spanish citizens. Al Saqq was arrested in the eastern city of Castellon.

Ghalyoun was previously arrested in April on charges of forming part of a network of businesses that sent profits to al-Qaida organizations.

He was initially let go due to insufficient evidence to support the charges. A police statement released Tuesday indicated the incriminating videos were seized during the earlier arrest.

According to the interior ministry, Ghalyoun shot five of the tapes during a 1997 visit, recording images of buildings, installations and monuments “that have been or are al-Qaida targets.”

“The style and duration of the recordings far exceed tourist curiosity,” it said. “For example, two of the tapes are like a documentary study, with innumerable takes from all distances and angles of the Twin Towers in New York.”

The five tapes also contain plenty of images of the Statue of Liberty, the Brooklyn Bridge and the Golden Gate Bridge, “whose suspension pillar is given substantial attention.”

Shots show interior and exterior areas of “a New York airport” as well as the Sears Tower, Disneyland and Universal Studios in southern California, police said. They did not identify the airport.

Another two videotapes with “extremely violent content” show terrorist training exercises and combat in Chechnya, as well as unnamed suicide attackers and donations for radical Islamic causes, they said.