CENTENNIAL, Colo. -

A security guard at Arapahoe High School says safety problems persist at the school nearly a year after a student fatally shot a classmate before killing himself.

Christina Erbacher-Kolk, who was working during the Dec. 13 shooting, wrote on Facebook Tuesday that school officials took no action after she and another guard told them 18-year-old Karl Pierson was looking at guns on a computer before the attack.
    
Erbacher-Kolk confirmed to The Associated Press she wrote the entry. She declined to comment further.
    
Erbacher-Kolk also says faulty security cameras and doors are not properly functioning since the shooting.
    
Erbacher-Kolk says administrators accused her of violating protocols and placed her on leave in retaliation for bringing up security problems.
    
Littleton Public School officials did not immediately return calls for comment.