A video of the incident may also follow the report to help train law enforcement agencies

September 10, 1999
Web posted at: 12:53 a.m. EDT (0453 GMT)

LITTLETON, Colorado (CNN) -- Police investigating the April 20 assault at Columbine High School say that although their final report is not yet ready, evidence leads them to conclude that only two gunmen participated in the assault.

The incident at Columbine High was the deadliest high school shooting in U.S. history. Investigators say two students -- Dylan Klebold and Eric Harris -- killed 12 other students and a teacher before taking their own lives.

Authorities expect their summary of the investigation to be 200 to 300 pages long. They probably won't release the entire report "because it will be volumes," said Jefferson County Sheriff's Office spokesman Steve Davis.

"With everything that we know to date ... there's no indication that there were any other participants other than Harris or Klebold to carry this out," said Davis. "There's no physical or concrete evidence to point to (other assailants) as of yet."

Davis told CNN the department is considering producing and releasing a lengthy video detailing the attack at the Littleton, Colorado, high school and the police response.

In the days immediately following the attack, about 80 investigators were assigned full time to the investigation; that number has since dwindled to about 12, Davis said. Investigators have followed about 4,000 leads and have conducted at least twice as many interviews, he said.

Davis said ballistic reports have been completed, and "there are no unaccounted for rounds." All of the bullets recovered at the scene were fired from guns used by the two students or police, he said.

Barring any new information, Davis said he expects investigators to be unanimous in their opinion that only two gunmen were involved. "Everyone's on the same page."

As for earlier statements by Sheriff John Stone that he believed more people were involved, Davis said: "I think the sheriff was speaking instinctively. It was hard for anyone to fathom that this whole incident was planned and executed by any two people."

Davis said he hopes the final investigative report will be released late this year.

"My understanding is the families of the victims will be given the information first, before it's made public. I think that's only right," Davis said.

Davis said investigators also want to produce a video to accommodate a "phenomenal" number of requests from other law enforcement agencies for details about the incident and the emergency response.

"This video might even be used as a training type of format for other law enforcement agencies," Davis said. "Everybody kind of likes the idea. Whether it happens or not, I don't know. I have a good feeling it will."

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