It all started falling apart on the streets of Boston yesterday -- when agents and police killed one suspect -- Usaama Abdullah Rahim -- after, they say, he lunged at them with a knife.
Last night, an alleged accomplice was arrested -- David Wright was charged with conspiring to obstruct a federal investigation by destroying evidence.
The week before his fatal encounter with law enforcement, investigators say Rahim bought the knife he pulled on Boston police and FBI agents.
Court documents say that on May 25, Rahim went on Amazon.com and bought a marine fighting knife with a 10-inch blade, as well as a knife sharpener.
The next day Rahim, who was under surveillance, called David Wright. The FBI recorded the call and believe the men were speaking in code about a plot to kill.
Rahim told Wright, "I just got myself a nice little tool...it's good for carving wood and like, you know, carving sculptures."
Rahim then told Wright something was "like thinking with your head on your chest" -- an apparent reference to beheadings carried out by the Islamic State of Iraq and Syria (ISIS).
On May 27, FBI agents intercepted the Amazon package and X-rayed it before it was delivered.
That same day, court papers allege, Rahim went back on Amazon and purchased another knife. He would buy a total of three.
Then, this past Sunday, May 31, Rahim and Wright went to a beach in Rhode Island and met with a third person to discuss their plans to behead someone.
But yesterday, investigators say, the plan changed. At 5 a.m. Rahim called Wright and told him he was planning an immediate attack on police.
According to the recorded calls, Wright said, "You're attempting to go on vacation I see," a terrorist code for committing Jihad. Rahim replied, I'm just going to go after them, those boys in blue."
That prompted law enforcement to act. Shortly after 7 a.m., in a drug store parking lot, FBI agents and Boston police tried to question Rahim. Police say Rahim pulled one of the knives on the officers and threatened him.
Boston Police Commissioner William Evans says a surveillance camera nearby shows what happened next.
"...And then all of a sudden you see five FBI agents and Boston retreating, backing on their feet with their hands up...and from the witnesses accounts, from officers' accounts, giving commands, 'drop the weapon, drop the weapon,' and then unfortunately we see the suspect shot."
That surveillance tape was shown Wednesday to members of Boston's Muslim community. They said it clearly shows that Rahim was not shot in the back, as alleged by his family. But the video is too far away to draw any further conclusions about his interactions with law enforcement.
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