PORTLAND, Ore. (CN) - Undercover FBI agents testified Wednesday that they were "testing the resolve" of Mohamed Mohamud, the alleged "Christmas tree bomber," by giving him menial tasks to make what turned out to be a fake bomb.
Mohamud, now 21, is on trial for attempted use of a weapon of mass destruction. He faces up to life in federal prison if convicted.
Prosecutors claim Mohamud picked the time, date and place of the bombing, planned for "Black Friday," the day after Thanksgiving in 2010.
His defense attorneys claim the FBI induced him into the plot he never would have tried without the FBI involvement.
The two undercover agents assigned to Mohamud testified this week about their meetings with him in the months before his arrest.
U.S. District Judge Garr King cleared the courtroom for the undercover agents' testimony. The public watched on closed-circuit television.
Both men used pseudonyms and wore light disguises in court. The public was not able to see them on the witness stand.
First to testify in this manner was "Youssef," who contacted Mohamud by email, posing as an al-Qaeda recruiter.
Youssef testified that the undercover operation was a way to see if Mohamud was serious about his plan, or whether it was "just talk."
Public defender Lisa Hay briefly cross-examined Youssef on Wednesday, asking him about the $2,800 the FBI paid Mohamud to rent an apartment.
In a recording, Youssef is heard telling Mohamud about the "brothers" overseas who made it possible for him to have the money.
"Some of them die. Some of them sweat. Some of them bleed," Youssef said.
Joining Youssef undercover was "Hussein," who posed as an explosives expert. The two men met with Mohamud several times between August and November of 2010.
Hussein testified that he is a Muslim who was born and raised in an Arabic-speaking country. He said he has worked in counterterrorism since 2003 and has more than 20 years of experience in law enforcement.
The jury saw and heard secretly recorded video footage of the agents talking with Mohamud.
The agents, on examination by prosecutor Pam Holsinger, said they gave Mohamud many opportunities to back out of the bomb plot, but he stood firm.
Youssef and Hussein directed Mohamud to buy items such as a toggle switch, a timer and wires, according to evidence.
The agents said Mohamud's plan was to detonate the truck bomb at Pioneer Courthouse Square during the Christmas tree-lighting ceremony in Portland, then speed off to Corvallis, where he would stay in a hotel before leaving for Yemen.
To bolster the plan to make a fake passport, the agents said, they asked Mohamud for headshots and a fake name that he supplied - Beau Coleman.
"I want whoever is attending that event to leave either dead or injured," Mohamud said in one wiretap recording presented at trial.
The agents took a trip with Mohamud to rural Lincoln County to detonate a small bomb. The bomb was fake, but another agent switched it out with a real one before Mohamud dialed a cell phone to detonate it, according to testimony.
"We wanted him to understand the magnitude of what he wanted to do," Hussein said.
In one recording, Youssef asks Mohamud if he had ever "seen a person's insides," referring to the carnage of the bomb plot.
Mohamud said he had watched videos of beheadings in Iraq and "it doesn't bother me."
But when Youssef asked Mohamud if he thought he could cut off someone's head, he said, "It's different in real life."
The trial is expected to take about five weeks.
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