In the months before the mass shooting in a Colorado movie theater, James Holmes withdrew from his already small social circle into a near solitary existence.
His limited interactions with other neuroscience students during this phase of heightened isolation included showing off a semiautomatic gun to one and sending a text message in which he suggested he was afflicted by a form of bipolar disorder, according to a detailed report by The New York Times.
While Holmes' behavior was troubling to University of Colorado classmates and officials who spoke to The Times, it appears none of them feared he would harm others.
Still, about two weeks before the July 20 rampage at a midnight screening of "The Dark Knight Rises," he warned a fellow grad student via a text message to stay away from him, "because I am bad news."
That admonition came after Holmes, 24, questioned the unnamed woman about dysphoric mania, a form of bipolar disorder, The Times learned. During the back-and-forth messaging, Holmes suggested that he had controlled the disorder by taking medication.
In May, Holmes displayed a semiautomatic Glock pistol and told another student he bought it to protect himself, according to The Times. The weapon could have been one of the four that prosecutors allege was part of the arsenal that Holmes amassed over several months.
The latest fragments revealed about Holmes -- the suspect in last month's shooting that left 12 people dead and 58 wounded in Aurora -- depict a loner, but do not pinpoint a particular motive for the outburst of violence.
Classmates and neighbors have previously said that Holmes was painfully shy, averted eye contact and prone to socially awkward statements. Yet until this spring when his personality darkened, others could still coax a pleasant remark from him.
The search for an explanation has been elusive. Arapahoe County District Chief Judge William Sylvester issued a gag order preventing the release of some documents about Holmes. His parents have declined to speak about him.
His psychiatrist, Dr. Lynne Fenton, who reportedly voiced concerns about him to a university safety committee and asked the campus police to check for a criminal record, has also kept silent.
But prosecutors trying to prove that Holmes carefully planned the shooting allege that he told a student in March that he wanted to kill people. They also contend that Holmes threatened a professor in June around the time he flunked an oral exam and dropped out of the program.