US shooter may have mailed advance warning of his massacre

James Holmes, the accused gunmen in last Friday's movie carnage in Colorado mailed a notebook "full of details how he was going to kill people to a psychiatrist at the University of Colorado where he had been a student until dropping out last month, Fox News reported.

Holmes walked into a theatre in Aurora dressed in riot gear and brandishing at least three weapons at the front of "The Dark Knight Rises" movie premiere around midnight on Friday. He allegedly set off two smoke bombs before opening fire on the movie theater patrons with an assault rifle, shotgun and a handgun, killing 12 people.

The TV network reported that the notebook had full details and drawings and illustration of how he was going to carry out the massacre and the mail was found only during the search of university mailroom.

Among the images shown in the spiral-bound notebook's pages were gun-wielding stick figures blowing away other stick figures, the channel quoted police as saying.

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.

A second law enforcement source said authorities got a warrant from a county judge and took the package away. When it was opened, its chilling contents were revealed.

Fox News said the package had been in the mailroom since July 12, though another source who confirmed the discovery to could not say if the package arrived prior to Friday's massacre. It was not clear why it had not been delivered to the psychiatrist.

The notebook is now in possession of the FBI.

The university has not confirmed the existence of the note, but issued a statement saying that the "Colorado Anschutz Medical Campus can confirm that the suspicious package discovered at the Facilities Services building on Monday, July 23, 2012, was delivered to the campus by the United States Postal Service that same day."

Discovery of the package prompted the evacuation of the building for about 90 minutes. The school also refused to say whether Holmes was seeing a psychiatrist.

The detail of the mailed notebook adds to other information emerging about Holmes' troubles at the University of Colorado, where he spiraled down from a successful and apparently happy student to an accused mass murderer in a matter of months.

He reportedly struggled academically in the PhD programme he enrolled in last fall.