The Jefferson County (Colo.) Sheriff's office is still under investigation for the way it handled complaints about the two teenagers who killed 12 classmates and a teacher at Columbine High School in Littleton, Colo., before committing suicide. Many still believe that the Sheriff's Office should have been able to predict and prevent the killings.

Several investigations have been conducted since Eric Harris and Dylan Klebold brought guns and pipe bombs to school to execute their plan.

While new pieces of evidence were introduced as recently as six months ago and some victims' families have won damages in lawsuits against the sheriff's department, the school district, and the killers' parents, there is no real answer to what happened, nor an expectation that those affected by the event will find closure anytime soon.

For many, the day marking the fifth anniversary of the 1999 school shooting in Colorado was not about blame. People who gathered on the campus, which was closed to commemorate the day, remembered those who died and used the time for peaceful reflection.

"I really don't think we are going to get any more answers," Al Velasquez, whose son, Kyle, was among those killed, told the Associated Press.