MIAMI -- A Saudi national who the FBI issued a worldwide alert for Thursday, and who reportedly lived in South Florida for several years, may be linked to a plot to set of a radioactive dirty bomb.

A federal law enforcement source said Adnan El Shukrijumah has been linked to Jose Padilla, an American citizen accused of plotting to detonate a dirty bomb -- an explosive device that can spread radioactive material.

The source said authorities were tipped to the Saudi suspect by Khalid Shaikh Mohammed, a top al-Qaida official who was arrested March 1 in Pakistan.

The source said officials got information after the arrest that refers to Padilla and El Shukrijumah, who once lived near each other in the Miami area.

Padilla is being jailed as an enemy fighter. Federal officials say El Shukrijumah has gotten flight training and has a Florida driver's license.

FBI Sounds Alert

The FBI is asking for help from law enforcement and the public in locating El Shukrijumah, who may still be plotting terrorist attacks as part of al-Qaida.

His current whereabouts are unknown, but on Thursday agents searched the Miramar neighborhood near the Southwest 27th Street home that he had reportedly lived in with his parents and brother. The home is connected to another house next door that Channel 10 News learned has been used for "religious purposes."

Nabil El Shukrijumah, who lives in the home, has told the FBI he is Adnan's brother. He has also said Adnan left the United States years ago and now lives with family in Morocco.

"El Shukrijumah is possibly involved with al-Qaida terrorist activities and, if true, poses a serious threat to U.S. citizens and interests worldwide," the FBI said in a statement. Sources tell Channel 10 News that there is a possibility that El Shukrijumah could be a "major operative."

A senior law enforcement official, speaking on condition of anonymity, said the FBI believes El Shukrijumah received flight training, possibly in Florida. The official said El Shukrijumah's organizing capabilities are comparable to those of Mohammed Atta, the suspected organizer of the Sept. 11 terror attacks.

El Shukrijumah is described as 27, about 5 feet 4 inches and 132 pounds or heavier. He may or may not be wearing a beard.

Although born in Saudi Arabia, the FBI said El Shukrijumah carries a passport from Guyana. He also could have passports from Saudi Arabia, Canada or Trinidad. And he has used a half-dozen aliases, according to investigators, including Adnan G. El Shukri Jumah, Abu Arif, Ja'far Al-Tayer, Jaffar Al-Tayyar, Jafar Tayar and Jaafar Al-Tayyar.

The FBI alert did not specify the nature of the threat El Shukrijumah may pose to U.S. interests. One FBI official said El Shukrijumah only recently came to the agency's attention, but the official did not say how.

If you see El Shukrijumah or have any information about him, you are asked to call the Miami office of the FBI at (305) 944-9101.