Thousands of Ontario elementary schools are adding new security measures as the provincial government expands its locked-door program in response to a tragedy at a U.S. school.

Before the start of the new school year, front-door buzzers and surveillance cameras are being installed in about 2,450 schools that applied for and received a share of $10 million in funding under a renewed provincial program.

That includes $465,000 to install “secure access systems” in the remaining 150 Toronto District School Board elementary schools that don’t have them, spokesman Ryan Bird told CP24.

Almost 3,300 Ontario elementary schools have received funding under the Safe Welcome Program since it was first used in 2005, said Lauren Ramey, a spokeswoman for Education Minister Liz Sandals.

That accounts for about 80 per cent of the province’s elementary schools.

Sandals said the security systems will allow staff in a school's office to see visitors are the front door and have a conversation with them via an intercom to find out why they are there.

Staff would then decide whether to let the person or people inside the school, Sandals told CP24 reporter Jamie Gutfreund.

Sandals said many newer schools don't require the setup because they are designed so that the office is next to the front entrance, and staff can see people when they enter the building.

Any school that receives funding is required to lock their front and perimeter doors during school hours to restrict visitors’ access in an effort to keep kids safe, Ramey told CP24.

All school boards are required to develop, implement and practice lockdown procedures in partnership with the local police service, Ramey said.

Former Ontario premier Dalton McGuinty announced the funding last December in response to a shooting rampage that killed 20 children and six educators in Newtown, Conn.

@ChrisKitching is on Twitter. For instant breaking news, follow @CP24 on Twitter.