CNN used footage for Sandy Hook that was not from Sandy Hook

Have a look around the 1:00 mark on this CNN report and read on:

As the reporter is saying "they arrived to carnage", in reference to the carnage of the alleged Sandy Hook Elementary school shooting, CNN cuts to footage of seven police officers charging forward. Basically, this scene:

So what's the problem?

The school in the background is St. Rose of Lima School, not Sandy Hook Elementary School. A close examination of the landscaping, parking lot markings, and the distinct curvature of the sidewalk reveals the discrepancy in the footage.

Have a look:

Oh look, it's St. Rose of Lima School:

Which looks nothing like Sandy Hook Elementary:

What the hell were police officers and a film crew doing at St. Rose of Lima and why were they charging across a parking lot? Was this footage shot during the alleged school shooting at Sandy Hook?

We want answers!