NEW YORK (AFP) - The house where the killer responsible for one of the worst mass school shootings in US history lived and began his murder spree has been demolished, officials confirmed Wednesday.

The demolition of the sprawling white-timbered property will leave the lot empty. Local media reported the proceeds of any future sale would go to families of the victims.

Adam Lanza, 20, shot dead his mother as she lay in bed at the house before heading to Sandy Hook Elementary School and killing 26 others - 20 of them young children - on Dec 14, 2012.

An official at Newtown council in the northeastern state of Connecticut confirmed the demolition to AFP.

"It's just a reminder to the neighbours and the town. It's better to have it not be a constant sign of what happened," George Benson, Newtown director of planning, told news channel WFSB.

Resident Dorothy Dwyer welcomed the demolition.

"It's only a bad memory and we have people stopping there that really shouldn't stop there and it's a nice area, and those people deserve to have privacy," she told the same channel.

The house was turned over to the town council after it had been foreclosed by a bank.

US councillors in Newtown voted unanimously in January to tear it down.

The school was demolished in 2013.