(NEWTOWN, Conn.) -- Two adult survivors who were shot and injured in the Newtown, Conn., school massacre will be integral parts of the investigation into the deadly rampage, police said on Monday.
"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," Connecticut State Police Lt. Paul Vance said at a news conference Monday.
Both survivors are recovering from gunshot wounds in the hospital, police said. Authorities had previously mentioned one adult survivor. The adults have not been identified and police did not give details on their condition.
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 before turning the gun on himself.
Lanza also killed his mother Nancy Lanza at the home they shared before going to school.
"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."
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.
"Any interviews with any children will be done with professionals...as appropriate," Vance said. "We'll handle that extremely delicately when the time arises."
The first funerals for victims of the shooting are on Monday, beginning with 6-year-olds Noah Pozner and Jack Pinto.
Officials said on Monday that the Sandy Hook Elementary School, where the shooting took place, will be closed "indefinitely."
Both the school and the home where shootings took place are being held by police as crime scenes, and Vance predicted authorities would spend "months" investigating the elementary school.
All Newtown schools are closed on Monday to give residents more time to cope. Every school except for Sandy Hook is expected to re-open on Tuesday.
The town of Monroe has offered to open Chalk Hill School, which is not currently being used, to Sandy Hill students and staff, the Newtown Board of Education said in a statement.
The neighboring community's school is expected to be ready to accommodate students in the next few days, though an exact schedule has not yet been published.
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