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By Teresa Carson
PORTLAND, Ore., Jan 14 (Reuters) - Testimony in the trial of a Somali-born man charged with trying to bomb a Christmas tree event in Oregon opened on Monday with an FBI agent saying the accused first aroused concerns by discussing martyrdom in email exchanges with Islamist militants.
Miltiadis Trousas, supervisor for the FBI sting operation that led to the arrest of Mohamed Osman Mohamud two years ago, testified that the defendant came to authorities' attention through intercepted communications with "some dangerous people overseas."
But under defense cross-examination, Trousas acknowledged that authorities lacked any evidence that Mohamud had actually sought bomb-making instructions or materials until after he first met with undercover FBI agents in July 2010.
Mohamud, a naturalized U.S. citizen and former Oregon State University student, faces life in prison if convicted on a charge of attempting to use a weapon of mass destruction in a plot to blow up a Christmas tree-lighting ceremony in Portland in November 2010. He was 19 at the time.
An FBI affidavit filed in the case says Mohamud was taken into custody after he tried to use a cell phone to trigger what he believed was a car bomb but was actually a harmless device supplied by agents posing as operatives for Islamist extremists.
The fake bomb was planted in a van near a downtown square lined with shops and offices and crowded with thousands of people attending the holiday festivities.
But defense attorney Stephen Sady has argued that his client, now 21, is a victim of government entrapment and would never have tried to carry out the bombing on his own.
The FBI "created a crime that would have never happened without them," Sady said in opening statements on Friday.
As the prosecution's first witness on Monday, Trousas outlined the origins of the FBI probe, starting with testimony about email messages that he said investigators found troubling.
Among those Mohamud was found to have corresponded with was Samir Khan, who ended up being killed in a September 2011 CIA drone strike in Yemen along with another U.S.-born al Qaeda militant, Anwar al-Awlaki, Trousas told jurors.
Khan, according to U.S. intelligence, had served as editor of "Inspire," a propaganda and recruitment publication for Al Qaeda in the Arabian Peninsula, the group's Yemeni branch.
In some of his email exchanges, Mohamud made statements expressing that "he wanted to become a martyr, and "that was of great concern to us," Trousas testified.
Trousas said Mohamud's father also had alerted the FBI to worries that his son was becoming radicalized, and investigators set out in the summer of 2010 to assess Mohamud's intentions through an undercover investigation.
In Mohamud's first encounter with FBI agents posing as Islamist militants, Trousas testified, they offered him several options to better support Islam - committing to prayer five times a day; continuing his studies to become a doctor or engineer; becoming a fundraiser; becoming "operational" or becoming a "martyr."
Trousas testified that if Mohamud had chosen one of the first two options the FBI would have halted the operation immediately, but instead he told agents he wanted to become "operational."
One of the two undercover agents, who had pretended to be an al Qaeda recruiter and was identified in court only by his pseudonym, Youssef, later took the stand to recount his first face-to-face meeting with Mohamud in the lobby of a downtown Portland hotel.
The agent acknowledged that he failed to capture the conversation on tape because his hidden audio-recorder malfunctioned. But he testified that when Mohamud was asked what he was willing to do for "the cause," the defendant told him that he had "planned to wage war in the United States."
Their meeting ended with Youssef telling Mohamud to research possible targets for attack in Portland. Less than two weeks later, the agent testified, he received a poem written by Mohamud titled "The Dear Martyr Whose Story I Shall Tell," containing the line: "Oh, woe to the Christians, my dagger hits his chest."
Spectators and members of the media were ordered out of the courtroom and into a nearby chamber to watch the proceedings on closed-circuit television during testimony by the agent, whose face remained off camera to protect his identity. (Reporting by Teresa Carson; Writing by Steve Gorman; Editing by Cynthia Johnston and Lisa Shumaker)