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A suburban Chicago teenager has been arrested on terrorism-related charges and accused of seeking to join an Al Qaeda-affiliated group in war-torn Syria, the FBI announced Saturday.

Abdella Ahmad Tounisi was arrested Friday night as he attempted to board a flight from Chicago's O'Hare International Airport to Turkey, which borders Syria, the FBI said. He hoped to join Jabhat al-Nusrah, a group fighting Syrian President Bashar Assad's regime in a bloody civil war.

There are no links between Tounisi and the Boston Marathon bombings earlier in the week, the head of the FBI office in Chicago, Cory B. Nelson, said in a statement announcing the arrest.

Tounisi, a U.S. citizen, was snared in an Internet sting after contacting a sham website set up by the FBI that purported to hook up would-be fighters with terrorists, the federal complaint says.

The 18-year-old Aurora man was surprisingly frank about his lack of fighting experience.

"Concerning my fighting skills, to be honest, I do not have any," he allegedly wrote in one email written this year, according to the complaint. "I'm very small ... physically but I pray to Allah that he makes me successful."

At the top of the website were the words, "A Call for Jihad in Syria," and the site invited interested parties to "come and join your lion brothers ... who are fighting under the true banner of Islam." Elsewhere, the site advised users on how to conceal their Internet tracks, the complaint says.

Email responses to Tounisi from an FBI agent posing as a terror-group recruiter referred to Tounisi as "Brother Abdullah" and encouraged him not to despair about his lack of battle skills.

Tounisi is charged with one count of attempting to provide material support to a foreign terrorist organization. If convicted, he faces a maximum 15-year prison term.

FBI Special Agent Joan Hyde told MyFoxChicago.com that Tounisi was provided with a bus ticket that would take him from Istanbul to a city near the border of Turkey and Syria.

"The charges were a result of some online communications that he had with an undercover employee...Mr. Tounisi thought that the individual was a recruiter for the al-Nusra terrorist organization," Hyde told the station.

Tounisi was carrying out research online about Jabhat al-Nusrah, or Nursa Front, which is a well-organized rebel faction Assad's regime, the complaint says. In late 2012, the U.S. government designated the group a foreign terrorist organization, describing it as an alias for the group Al Qaeda in Iraq.

According to the complaint, Tousini's Internet searches included the keywords "martyrdom operations," as well as the phrases "providing material support what does it mean" and "Terrorism Act 2000" — a possible indication that he was concerned about the legal implications of what he was contemplating.

Neither the complaint nor the FBI statement includes the name of an attorney for Tounisi. And there was no public telephone listing for a Tounisi in Aurora, which is just west of Chicago.

The complaint says Tounisi was a close friend of Adel Daoud, a Chicago-area teen who was arrested last year on charges he sought to detonate a device he thought was a bomb outside a downtown bar.

Daoud has pleaded not guilty and is in jail awaiting trial. Daoud's attorney, Thomas Durkin, has raised questions about whether agents employed improper methods in a bid to woo or trick Daoud into committing crimes.

The complaint does not accuse Tounisi of participating in the alleged attack planned by Daoud, though it does contend the two friends discussed possible targets before Daoud's arrest. The complaint in Tounisi's case also does not include new allegations against Daoud.

Tounisi allegedly toyed with the possibility of joining Daoud's alleged plot, the complaint says. But the filing adds that Tounisi eventually opted out when he concluded Daoud's contact may have been working for law enforcement. In filings after Daoud's arrest, prosecutors did say the contact was an FBI informant.

"Tounisi's interest in violent jihad continued, notwithstanding Daoud's arrest," the complaint says.

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The Associated Press contributed to this report.