according to caller ID, its Bob Pecoroni MA and is a unpublished number according to Qwestdex.com

We have received several calls from 218-963-7811 which were a "threatening" voice message stating we "must call them back immediaetly to resolve this problem" and we have not returned their calls, etc.

Apparently the call also tried to login to our phone system and call 905-413-8577 in ONTARIO.

We are a USA public school, so why would we be receiving this type of phone call?

this is the secret phone number for global credit. If you receive nasty phone messsages stating that you need to call back 866-350-4275, DONT.....
I called back this 866 number and the 218 number appeared on my caller ID. This is a collection agency for Capital One plus other banks. These people are so very rude and will continue to harass you. They will reach out to you for another family member, etc. They will continue to threaten you, you need to complain to the FTC.