The FBI has released documents containing details of its investigation into the 1970 bombing of Sterling Hall.
Since the FBI is required to release a person's file after they die, the files were released to the Associated Press following the death of one of the bombers, Dwight Armstrong, in June.
Armstrong's brother, Karl Armstrong, and friend David Fine were also convicted for being involved in the bombing and served short prison sentences. Another suspect, Leo Burt, is still at large.
The majority of the information presented in the more than 600 pages released to the Associated Press is not new.
However, the files expose the urgency with which the FBI investigated the bombing that resulted in the death of 33-year-old researcher Robert Fassnacht and caused millions of dollars in damage.
A week after the bombing, the FBI sent a memo that emphasized the importance of solving the crime quickly before it could ""trigger similar tragic consequences elsewhere.""
The files detail the FBI's national search for the bombers and how it identified the fertilizer used for the bombing in a van.
