The stories of James Holmes' bizarre behaviour before and after Friday's Colorado movie theatre shooting continue to mount.
In a strange twist, it appears the accused gunman mailed a notebook "full of details about how he was going to kill people" to a University of Colorado psychiatrist prior to the attack.
According to a source who spoke exclusively to Fox News, police and FBI agents were called to the University of Colorado Anschutz Medical Campus in Aurora on Monday morning after the psychiatrist, who is also a professor at the school, reported receiving a package believed to be from the suspect. Although that package turned out to be from someone else and harmless, a search of the Campus Services' mailroom turned up another package sent to the psychiatrist with Holmes' name in the return address.
"Inside the package was a notebook full of details about how he was going to kill people," the source told FoxNews.com.
"There were drawings of what he was going to do in it — drawings and illustrations of the massacre."
Among the images shown in the spiral-bound notebook's pages were gun-wielding stick figures blowing away other stick figures.
The source said the package had been in the mailroom since July 12, though another source who confirmed the discovery to FoxNews.com could not say if the package arrived prior to Friday's massacre.
Holmes was enrolled in the neuroscience doctoral program at the University of Colorado until June when he dropped out after failing a key oral exam.
It could not be verified, however, if the psychiatrist had had previous contact with the suspected shooter.
Holmes, 24, is being held without bond at the Arapahoe County jail in connection with the shooting, which left 12 people dead and 58 injured.
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Officials say that since his arrest Holmes has been displaying odd behaviour.
According to ABC News, in the hours after his arrest Friday, he stared at the wall in the Arapahoe Police Headquarters with his eyebrows twitching.
Holmes told police he was the fictitious Batman villain, the Joker, and when cops put evidence bags over his hands to preserve traces of gunpowder residue, he pretended the bags were puppets.
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During his first court appearance on Monday, Holmes appeared sedated making bizarre movements with his eyes and forehead throughout the duration of the 15 minute hearing.
His next court appearance is set for July 30.
Plenty of sex before killing
According to the U.K.'s Sun newspaper, Holmes was a follower of the "teachings" of Norwegian mass killer Anders Breivik.
Holmes even signed up on an adult contact website in a bid to follow Breivik's advice to "keep up morale" by having plenty of sex before his attack.
And according to the TMZ.com, he did.
TMZ has obtained information which may show Holmes was involved with multiple prostitutes in the months before the movie theatre attack.
"Holmes was no stranger to sex web sites ... and sources tell us he also frequented a message board where potential johns posted reviews for hookers in the Colorado area," notes TMZ.com.
"We found the message board ... and discovered several posts written under James' supposed screen name ... in which he details multiple sexual encounters with different prostitutes."
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