A US judge entered a plea of not guilty on behalf of alleged Aurora theater gunman James Holmes on Tuesday, after his lawyers said they were not ready to enter a plea.
The judge left it open for lawyers for the 25-year-old to enter a plea of not guilty by reason of insanity at a later date, at Holmes's arraignment for the killing of 12 people in the Colorado town of Aurora last July, AFP reported.
Judge William Sylvester set a trial date for August 5.
Defense attorney Daniel King said he would be ready to make a plea by May 1 or June 1. Prosecutors objected and said they had waited long enough, to which the judge agreed and entered a standard not guilty plea.
Holmes is accused over the July 20 massacre at a midnight screening of the Batman movie, "The Dark Knight Rises," which revived America's perennial debate about gun control.
Witnesses said Holmes threw smoke bomb-type devices before opening fire randomly with weapons, including an AR-15 military-style rifle, a 12-gauge shotgun and a .40-caliber pistol.
Holmes' arraignment had initially been scheduled for January, but the judge agreed at that time to delay it, triggering anger from some of the victims' relatives.