HARTFORD, Conn. (AP) -- The prosecutor who led the investigation into the Newtown school shooting says it did not determine a motive for the attack.
State's Attorney Stephen Sedensky III says there is also no clear indication why he chose Sandy Hook Elementary School as the target for his rampage other than the fact that it was close to his home.
He said the gunman, Adam Lanza, had significant mental health issues that affected his ability to live a normal life and interact with others but did not affect his mental state for the crimes.
He said police went into the school within minutes of the first shots being fired and that along with the actions of teachers inside saved many children's lives.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
Investigators planned to release a long-awaited report Monday on the Newtown school shooting that could provide some of the first official answers to questions about the history of the gunman and the police response to one of the worst school shootings in history.
The summary report by the lead investigator, State's Attorney Stephen Sedensky III, comes nearly a year after the massacre of 20 children and six women inside Sandy Hook Elementary School.
The Dec. 14 shooting plunged the small New England community into mourning, elevated gun safety to the top of the agenda for President Barack Obama and led states across the country to re-evaluate laws on issues including school safety.
The report expected Monday afternoon will not include the full evidence file of Connecticut State Police, which is believed to total thousands of pages. The decision to continue withholding the bulk of the evidence is stirring new criticism of the secrecy surrounding the investigation.
Dan Klau, a Hartford attorney who specializes in First Amendment law, said the decision to release a summary report before the full evidence file is a reversal of standard practice and one of the most unusual elements of the investigation.
"What I found troubling about the approach of the state's attorney is that from my perspective, he seems to have forgotten his job is to represent the state of Connecticut," Klau said. "His conduct in many instances has seemed more akin to an attorney in private practice representing Sandy Hook families."
Sedensky said he could not comment.
Twenty-year-old Adam Lanza killed his mother inside their Newtown home before driving to his former elementary school, where he fired off 154 shots with a Bushmaster .223-caliber rifle within five minutes. He killed himself with a handgun as police arrived.
Warrants released in March detailed an arsenal of weapons found inside the Lanza home. But authorities have not provided details on the police response to the shooting, any mental health records for Lanza and whether investigators found any clues to a possible motive for the rampage.
Sedensky has gone to court to fight release of the 911 tapes from the school and resisted calls from Connecticut's governor to divulge more information sooner.
The withholding of 911 recordings, which are routinely released in other cases, has been the subject of a legal battle between The Associated Press and Sedensky before the state's Freedom of Information Commission, which ruled in favor of the AP, and now Connecticut's court system.
New Britain Superior Court Judge Eliot Prescott said Monday he will listen to the 911 recordings from the school before ruling on whether they can be publicly released. He said his ruling would not come Monday.
If the recordings are released, the AP would review the content and determine what, if any, of it would meet the news cooperative's standards for publication.