(NEWTOWN, Conn.) -- A computer at the Connecticut home where Newtown, Conn., school shooter Adam Lanza lived with his mother was badly damaged, perhaps smashed with a hammer, said police who hope the machine might still yield clues to the gunman's motive.
The computer's hard drive appeared to have been badly damaged with a hammer or screw driver, law enforcement authorities told ABC News, complicating efforts to exploit it for evidence.
Officials have "seized significant evidence at [Lanza's] residence," said Connecticut State Police spokesman Lt. Paul Vance, adding that the process of sifting through that much forensic evidence would be a lengthy and "painstaking process."
Authorities also told ABC News that the weapons used in Friday's rampage at Sandy Hook Elementary School and the Lanza home, which left dead 20 children and seven adults including Lanza's mother Nancy, were purchased by his mother between 2010 and 2012. According to the Bureau of Alcohol Tobacco and Firearms, Lanza visited shooting ranges several times in recent years, and went at least one time with his mother.
Authorities also revealed Monday morning that two adult women shot during the rampage survived and their accounts will likely be integral to the investigation.
"Investigators will, in fact, speak with them when it's medically appropriate and they will shed a great deal of light on the facts and circumstances of this tragic investigation," Vance said at a news conference today.
Both survivors are women and are now home from the hospital after being shot, police said. Officials had previously mentioned just one adult survivor. The women have not been identified and police did not give details on their injuries.
Both adults, Vance said, were wounded in the "lower extremities," but did not indicate where in the building they were when they were injured.
"There are many, many witnesses that need to be interviewed," Vance said. "We will not stop until we have interviewed every last one of them."
Vance said the investigation could take weeks or months to complete. "It's not something done in 60 minutes like you see on TV."
Some of the other key witnesses will be children who survived the shooting spree by playing dead, hiding in closets and bathrooms and being rescued by dedicated teachers.
Moving trucks were seen outside Sandy Hook Elementary School this morning, as school officials prepare to move furniture and supplies to a vacant school in neighboring Monroe.
Sandy Hook itself will remain a secure crime scene "indefinitely," said Vance, and officials said that the Sandy Hook Elementary School will be closed "indefinitely."
The town of Monroe has offered to open to Sandy Hook students the Chalk Hill School, a former middle school that currently houses the town's EMS and recreational departments. Officials in Monroe, less than 10 miles from Newtown, say the building could be ready for students by the end of the week, but have not yet set a date to resume classes.
The first funerals for victims of the shooting are Monday, beginning with 6-year-olds Noah Pozner and Jack Pinto.
President Obama delivered an emotional address at an interfaith prayer vigil in Newtown on Sunday night, comforting the community.
Thousands came out of the prayer vigil where Red Cross members distributed stuffed dogs to children and adults wept in the auditorium.
Police say Adam Lanza, 20, forced his way into Sandy Hook Elementary School on Friday, spraying bullets on students and faculty. Lanza killed 20 children and six adults at the school before turning the gun on himself.
Lanza also killed his mother Nancy Lanza at the home they shared before going to the school.
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