Alleged Colorado shooter James Holmes reportedly sent a warning package to a psychiatrist at his former university with a notebook and drawings of his plans to massacre people.

Holmes, 24, is accused of shooting 12 people dead and wounding 58 more at a cinema on Friday in Aurora, outside Denver, as young moviegoers packed the first midnight screening of the latest Batman film, "The Dark Knight Rises."

Batman actor Christian Bale paid a low-key visit Tuesday to Aurora, Colorado to comfort victims of last week's shooting massacre, which occurred during a screening of his latest film.

Pictures posted on Twitter showed the Welsh-born actor at the Medical Center of Aurora, where 20 of the 58 people wounded in Friday's massacre are still receiving treatment, some of them in critical condition.

His hair dyed orange, eyes staring out blankly, presumed Colorado gunman James Holmes made a bizarre first appearance in court Monday, after a rampage in which he allegedly shot dead 12 people and wounded 58 others.

The deadly shooting frenzy occurred shortly after midnight at a movie theater in Aurora, Colorado outside Denver, as moviegoers packed the first screening of the latest Batman film, "The Dark Knight Rises."

There were tears for the victims, and cheers for those who prevented even more lives being lost, as the Colorado town of Aurora stood silent Sunday to grieve the Batman theater massacre.

Some 3,000 mourners gathered three blocks from the multiplex where James Holmes allegedly opened fire on those attending a packed midnight screening of "The Dark Knight Rises" on Friday, killing 12 and injuring 58.

Police in Aurora, Colorado, early Sunday dismissed suspicions that another person helped James Holmes prepared the massacre at a movie theater that left 12 people dead.

"There are multiple unconfirmed and inaccurate news reports about a second suspect," police spokeswoman Cassidee Carson said in a statement.