Adam Lanza’s hard drive was damaged beyond repair before the 20-year-old went on a shooting rampage in Newtown, Connecticut, leaving investigators fearful that they will never learn the motive for the school shooting that claimed 26 lives.

Connecticut State Police had met with FBI investigators in an attempt to extract clues from Adam Lanza’s hard drive but said it appears he destroyed it before leaving for the school, the Atlantic Wire reported. They said it appeared he took either a hammer or a screwdriver to it, badly damaging the computer.

Police said it appears that Lanza took special care not to leave any clues about his steps before the Connecticut school shooting or his reasons for the massacre.

“He was eliminating [investigators’] ability to figure out what websites he had gone to or who he might have been communicating with,” one investigator said.

Officials also said it appears that Lanza left no letters or notes explaining why he decided to target the school after shooting and killing his mother, Nancy Lanza, in the home they shared. As the first of the funerals began Monday, officials began talking to two of the only people to be wounded and still survive to learn more about how events transpired that day, the New York Times reported.

Police said they still planned to search all they could, including cell phones and game consoles, to find any information they could about Lanza’s motivations.

Though Adam Lanza’s hard drive provided no more insight into his motives for the shooting at Sandy Hook Elementary School, police have pieced together other clues. They know Lanza played violent video games and have learned that he had an apparent inability to feel pain — which psychologists said may be related to a disorder that also makes it difficult to feel empathy.