Last night I received 20 calls from the same automated system.  The numbers were all Area Code 248 and the prefix was 276.  The last four number were:

1165
1168
2543
1953
1954
1950
1169
9930

No Caller ID or Company identified.  Did not answer the phone.

within 15 mins I have received calls to my cell with no message- I did not pick up from 248-276-9930,248-276-1952,248-276-1168,248-276-1951, 248-276-1953