A U.S. citizen who had been researching remote controlled boats and commercial flight simulators was charged Thursday with joining Al Qaeda and conspiring to bomb European tourist resorts where Americans vacation, as well as U.S. government facilities and military bases there.

A federal grand jury indicted Christopher Paul, 43, of Columbus, Ohio. According to the indictment, Paul trained with Al Qaeda in the early 1990s, and he told members of the terror network in Pakistan and Afghanistan that he was dedicated to committing violent jihad.

"The indictment of Christopher Paul paints a disturbing picture of an American who traveled overseas to train as a violet jihadist, joined the ranks of Al Qaeda and provided military instruction and support to radial cohorts both here and abroad," said Assistant U.S. Attorney General Kenneth Wainstein.

“The indictment and arrest culminated a four-year investigation,” added FBI Special Agent Tim Murphy.

Click here to read the indictment (FindLaw pdf)

Paul is charged with three counts: Providing material support to terrorists; conspiracy to use a weapon of mass destruction; and conspiracy to provide support to terrorists. He faces up to 15 years in prison for the first count, up to life for the second, and up to 10 years for the third.

In court Thursday, Magistrate Judge Terence Kemp asked Paul if he understood the charges. "Yes, sir," Paul replied

Prosecutors asked that he be held without bond, and Kemp set another hearing Friday on the issue. Paul's lawyer, Don Wolery, did not return a message seeking comment before the hearing.

A law enforcement source told FOX News they've been actively investigating Paul for four years. He trained in the Al Qaeda camps in Afghanistan and Pakistan, where he learned to handle explosives. Up until his arrest, the source said he was researching remote controlled boats and commercial flight simulators

"The evidence has been accumulated throughout the globe, on three different continents," said William Hunt of the U.S. Attorney's Office.

Hunt also said officials never thought Paul would carry out any of his plans before they nabbed him.

"If we ever thought there was an imminent threat to the public, we would have taken action," Hunt said.

Sources said one of the keys to finding Paul was Iman Faris, the Al Qaeda member who was convicted of conspiring to blow up the Brooklyn Bridge. The men were roommates in Columbus, Ohio, and linked to a third man who also faces terrorism charges.

"Mr. Faris did agree to provide assistance," Hunt said. "Whether that has anything to do with this case, I cannot comment."

Law enforcement sources makes an important distinction about Paul, pointing out that he traveled to the camps and stayed in an Al Qaeda guesthouse, only used for members of the network. He was a "made" man to pledged his loyalty to the cause.

The indictment says Paul traveled to Germany about April 1999 to train co-conspirators to use explosives to attack European and U.S. targets, including government buildings and vacation spots frequented by American tourists. It does not address specific resorts or buildings that might have been targeted, but it gives U.S. embassies, military bases and consular premises in Europe as examples.

Paul later sent a wire transfer of $1,760 from a financial institution in the U.S. to an alleged co-conspirator in Germany, prosecutors allege.

A fax machine in him home contained names, phone numbers and contact information for key Al Qaeda leadership and associates, according to the indictment, issued Wednesday.

Paul also is accused of storing material at his father's house in Columbus, including a book on improvised land mines, money from countries in the Middle East and a letter to his parents explaining that he would be "on the front lines," according to the indictment.

His sister, Sandra Laws, answered the door at the home and said she and her father live there. She said the family will be speaking to Paul's attorney later Thursday and declined further comment.

No charges are expected against family members, authorities said.

A friend of Paul's, Hisham Jenhawi, 32, said he found the charges hard to believe.

"I don't think it's even close to his personality to act upon something like that," he said at the courthouse. "He's a very kind person. You would meet him on the street and he would want to hug you with the heart that he has."

Paul was born Paul Kenyatta Laws. He legally changed his name to Abdulmalek Kenyatta in 1989, then to Christopher Paul in 1994, according to the indictment.

Two other Columbus men have been charged in federal investigators' terrorism investigation. Iyman Faris was sentenced in 2003 to 20 years in prison for a plot to topple the Brooklyn Bridge. Nuradin Abdi, accused of plotting to blow up a Columbus-area shopping mall, is awaiting trial on charges including conspiring to aid terrorists.

FOX News' Catherine Herridge and The Associated Press contributed to this report.