A Somali-US man was found guilty of plotting to blow up a crowded US Christmas tree ceremony attended by thousands, despite his claims that he was trapped by an FBI sting operation.
A jury returned its verdict on Mohamed Mohamud, 21, after deliberating for less than a day following the nearly three-week long trial over the attempted 2010 attack in the northwestern US state of Oregon.
Lawyers for Mohamud, who faces up to life in prison for plotting to use a weapon of mass destruction, claimed he was tricked into the attempted bombing by undercover agents from the Federal Bureau of Investigation.
But Oregon prosecutors insisted that the young man actively participated in a plot that could have killed thousands attending the Christmas tree lighting ceremony on November 26, 2010, had the bomb been real.
"Mr Mohamud made a series of choices over a period of several years -- choices that were leading him down a path that would have ended in violence," Greg Fowler, head of the FBI office in Portland, said after the verdict.
"His actions showed little regard for the rights and responsibilities that come with being an American or respect for the lives that he was prepared to take," he added in a statement.
Speaking on the courthouse steps afterwards, prosecutor Ethan Knight said: "It's good to have closure on the case.
"It's also sad, in that this defendant's conduct impacted a number of people including his family," added the assistant US attorney, noting that the evidence showed there was "a significant threat and a dangerous situation."
Sentencing was set for May 14 at the federal US District Court in Portland, near the scene of the crime.
Mohamud's lawyers planned to appeal the verdict, according to The Oregonian newspaper.
In closing arguments Wednesday, defense lawyer Stephen Sady said Mohamud, who was first contacted by an undercover agent a year before the attempted bombing, was a troubled teenager led on by the FBI.
"He's not a threat," the publicly-appointed attorney said, cited by local ABC television affiliate KATU. "He's simply a person trying to live through a difficult adolescence.
"In America, the government cannot create a crime," he added.
At the start of the trial, an FBI agent who gave evidence in disguise maintained that Mohamud was prone to violence from the beginning and spoke of plans to "wage war" on the United States.
To test Mohamud's resolve, the agent -- who was posing as an Al-Qaeda recruiter named "Youssef" -- said that in his first meeting with Mohamud, he gave the then-teenager five examples of how he could be "a good Muslim."
According to Youssef, whose real name was withheld in court, Mohamud stopped short of the most extreme option -- martyrdom -- but chose violence over praying five times a day or raising money for militant groups.
FBI agent Fowler said the guilty verdict "highlights the difficult but important work that FBI employees do every day."
"In this country, everyone has a right to live, work and worship freely and without fear. FBI employees -- in Oregon and around the world -- find strength in preserving and protecting these core values," he said.
Fowler thanked the jurors, saying: "I know that they carried a heavy burden -- deciding the fate of a young man while balancing the needs for safety and justice.
"We greatly appreciate their service to their country."
US Attorney for the District of Oregon Amanda Marshall acknowledged the case had been difficult not only for Portland, but also for Mohamud's family and the Somali community.
"We are hopeful that this will bring closure and healing to all of us here in Portland, and to all of the families that attended the Christmas tree lighting," she added.