DENVER » The university once attended by a man accused of killing 12 people in a Colorado movie theater confirmed Wednesday that it received a suspicious package two days earlier that was turned over to authorities, but it wouldn’t confirm its contents or sender.

The University of Colorado, Denver said the U.S. Postal Service delivered the package to its medical campus Monday, and it was immediately investigated and turned over to authorities within hours.

Fox News’ website reported that former neuroscience graduate student James Holmes sent a notebook to the university containing scribblings of stick figures being shot and a written description of an upcoming attack. The package containing it was addressed to a psychiatrist at the school, the website reported. It was unclear if Holmes, 24, had had any previous contact with the person. The neuroscience program that he withdrew from on June 10 included professors of psychiatry.

He is accused of opening fire on a theater showing the new Batman movie, killing 12 people and injuring 58.

NBC News, citing unnamed sources, reported that Holmes told investigators to look for the package and that it described killing people. The FBI and other law enforcement agencies refused to confirm the reports to The Associated Press.

U.S. Postal Service spokesman David Rupert said the agency’s inspectors have no direct knowledge of the package reportedly containing the notebook. He said no one has contacted the Postal Service for assistance in the investigation.