Feds tie expired visa to associate of 'dirty bomb' suspect

In U.S. 6 years without visa, police say

MIAMI, Florida (CNN) -- A man arrested last week with alleged connections to "dirty bomb" suspect Jose Padilla has been in the United States on an expired visa since 1996, a law enforcement official told CNN Sunday.

The source, without elaborating, also said the federal government had evidence that Adham Amin Hassoun had "engaged in terror type activities in connection with Padilla."

Hassoun, 40, was arrested Wednesday night at a traffic stop and charged with an immigration violation. He is being held without bond at the Krome Detention Center in Miami. Hassoun is to appear at an immigration hearing sometime this week, but it was unclear if any evidence presented would be revealed publicly or remain under seal.

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Hassoun entered the United States on a tourist visa on September 10, 1989, and was later granted an extension and changed his status to student, the source said. The student visa, however, expired in 1996, and Hassoun was "out of status" from that point, the source said.

Hassoun's mother, a naturalized U.S. citizen from Pakistan, applied on her son's behalf for a green card at one point, but it was never approved.

Officials hope Hassoun can shed light on how Padilla, raised in Chicago, Illinois, by Puerto Rican parents, became a Muslim extremist. Hassoun and Padilla attended the same mosque, Masjid Al-Iman in Fort Lauderdale, Florida, for most of the 1990s and were reportedly friends.

Padilla is accused of being part of a plot to build and set off a "dirty" bomb -- a conventional bomb laced with radioactive material. But Time magazine reported, in an exclusive story, that Padilla had initially gone to al Qaeda planner Abu Zubaydah in Afghanistan with plans taken from the Internet for a nuclear bomb.

The plans, a senior Bush official told the magazine, were inaccurate. Zubaydah, now in custody at the U.S. army base at Guantanamo Bay, Cuba, sent Padilla away with instructions to think smaller and try detonating a "dirty bomb," the newsweekly reported.

Padilla was arrested May 8 on his return to the Chicago airport. He is in Justice Department custody at a navy brig in South Carolina, held as an "enemy combatant."

-- CNN Correspondent Susan Candiotti contributed to this report.