Investigators have also released audio recordings of a SWAT team member who sneaked into the building during the standoff, the "Today" show reported today.
"[It] looks like two canisters on the outside," the unidentified SWAT team member said in describing what he was seeing from his vantage point inside the building. "[It] looks like a propane bottle on the inside, sort of like two coffee cans. [They are] strapped to a propane canister. [He has a] flashing light in his left hand, almost like a death grip."
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Lee entered the Discovery Channel building in Silver Spring, Md., around 1 p.m. Wednesday, armed with a gun and wearing metal canisters that appeared to be explosive devices, police said.
The gunman took two Discovery Channel employees and a security guard hostage in the lobby. The rest of the building, including some 1,900 employees and a day care center on the first floor, was evacuated.
The hostage drama at the Discovery headquarters ended shortly before 5 p.m. A police sniper shot Lee dead when he pointed one of his guns at the hostages, Montgomery County, Md., Police Chief Thomas Manger said. None of the hostages were injured.
Authorities have since released additional details on the hostage situation, including the revelation that Lee was carrying two non-firing starter pistols. Neither the police nor the hostages knew the guns were incapable of harming anyone. The explosive devices he carried, however, were capable of causing fatalities, police say.
Police went to the home Thursday where they were told Lee lived. It is a rental in Wheaton, a section of Montgomery County.
Lee, 43, was originally from Maui, the second largest of the Hawaiian Islands. Former friends and classmates from Lahainaluna High School remember who he was but seem to have contrasting views of the suspect.
"[He was] easygoing, friendly and humble," former classmate Darci Mahon, told AOL News. "He got along with everyone, [and] he always had a smile for everyone."
Sean Kee, a classmate who attended school with Lee from ninth to 12th grade, remembers him differently.
"I ... had him in art class my last year," Kee said. "He was a good drawer, he could draw Marvel-style, [but] other than that, he was kind of a loner and [got] picked on. As a whole, he couldn't relate to those around him."
Following the death of his parents, Lee moved to San Diego.
Court records show Lee had been arrested in 2003, for smuggling a woman from Tijuana. Lee pleaded guilty in California federal court and was sentenced to 18 months in prison, CNN reports.
Lee's anger with the Discovery Channel's programming escalated over time and culminated in the hostage situation and ultimately in his own death.
Earlier this week, Jim McNulty, one of the three hostages freed by police, released a statement about the ordeal, in which he thanked police for "helping to ensure the safety" of his colleagues.
The investigation is ongoing, but police say they believe Lee was acting alone.