DENVER — A bullet found in the backpack of a student slain in the 1999 Columbine massacre was fired by one of the teenage gunmen, according to test results released Tuesday.
The student's mother asked for the new testing after the parents of another slain Columbine High School student alleged their son had been shot by a Denver police sergeant rather than one of the gunmen.
The Colorado Bureau of Investigation concluded the bullet lodged in a notebook in Corey DePooter's bag came from a 9-millimeter rifle fired by Eric Harris.
Using the markings left on the bullet as it spun out of the gun barrel, investigators ruled out the possibility that the bullet was fired from the gun of fellow shooter Dylan Klebold or one of the 12 guns used by authorities.
DePooter, 17, was one of 13 people shot by the gunmen in the April 20, 1999, shooting. Harris and Klebold then killed themselves.
Earlier ballistics tests had determined that two slugs found in DePooter's chest came from Harris' rifle. The backpack bullet was not discovered until August 1999, when DePooter's family asked for his belongings, Jefferson County sheriff's spokesman Jim Shires said.
In initial tests soon after the discovery, the bullet was tested against only four law enforcement weapons because of what Shires called an oversight.