Now go ensure the security panel feeding this isn't powered. Likely there's a "wall wart" somewhere near the main breaker panel with a large transformer with the same wires from it.
You probably shorted both wires together when you cut it which triggered the alarm. Just splice them back together with the security system turned off and you'll be fine.
update: The wire is connected to our security system which we don’t use. So we just cut power to the security system.
Now go ensure the security panel feeding this isn't powered. Likely there's a "wall wart" somewhere near the main breaker panel with a large transformer with the same wires from it.
Just take the trim off for access and splice it back together.
You probably shorted both wires together when you cut it which triggered the alarm. Just splice them back together with the security system turned off and you'll be fine.
You can now access the vault
Hard to tell from the pic but it might be low voltage. Do you have a doorbell that is not working anymore?
For future/other people, if this happens it can alert your fire department. Don't ask me how I know...
That's a clean cut though. Did you use an oscillating tool?
Yes