The Connecticut State Police report on the shooting at Sandy Hook Elementary School will be released at 3 p.m. Friday.

The report will run several thousand pages and has been “redacted according to law,” according to a state police press release.

The report on the murder of 20 first graders, six educators, and the shooter’s mother, will be released at http://www.despp2.ct.gov/

It will include text, photos, and 911 calls received by the state police.

The release of the document means the criminal investigation is complete.

Last month, Danbury State’s Attorney Stephen Sedensky III released his 43-page report which included a state police timeline of 20-year-old shooter Adam Lanza’s attack on the school and of communications between first responders. According to the report, the first police officer arrived at the school within four minutes of the first 911 call, and officers entered the school about six minutes later. Lanza shot and killed himself within one minute of the first police officer arriving at the scene, about 4 to 5 minutes before officers entered the school.

Sedensky’s report went on to describe Lanza as a deeply troubled young man who would only communicate with his mother, Nancy Lanza, by email for the three months leading up to the shooting.

When state police searched Lanza’s home they found a copy of “Amish Grace.” The book details the 2006 school shooting in Pennsylvania. There also were old newspaper articles detailing a school shooting in 1891. Both were in a drawer in the computer room where Lanza had smashed his hard drive and where the gun safe was located.

The gun safe contained an “Enfield” Albion bolt action .303 caliber rifle and was open when police arrived. There also were numerous boxes of ammunition strewn around the closet and the safe. There was black garbage bags taped on the windows.

Lanza’s computer included images of mass murders, which were broken down into categories by number of victims killed. It also contained several video clips of Eric Harris and Dylan Klebold, the pair who carried out the Columbine High School shooting. Police also found a Word Document of a screenplay that was presumably written by the shooter about four male characters who have a delusional discussion and all but one of them ends up being killed.

But none of the evidence collected at either crime scene seemed to point to a motive.

“The obvious question that remains is: Why did the shooter murder twenty-seven people, including twenty children? Unfortunately, that question may never be answered conclusively, despite the collection of extensive background information on the shooter through a multitude of interviews and other sources,” Sedensky said in his report.

Last week, the Sandy Hook Advisory Commission created by Gov. Dannel P. Malloy was split about whether it needed more information to complete its own report on the shooting.

Harold Schwartz, a psychiatrist and member of the commission, said the group needs more detail than what Sedensky provided in his report.

“For us to write a report on the basis of the information we have now, to me, feels almost embarrassing and sets us up for potential actual, real embarrassment if real information that we don’t have becomes available at a later date,” he said.

Schwartz asked whether the group could seek testimony from the shooter’s estranged father, Peter Lanza. He said it was not clear from Sedensky’s report whether he had refused to release records on his son to the authorities.

Sedensky, who sat in on the meeting but did not participate, was asked afterward if some of the records Schwartz had asked about would be included with the information state police are expected to release on the incident early next year. Sedensky said only that “Mr. Lanza did cooperate with the investigation.”