I have been receiving Calls from this number for the last 3 weeks.

If I let it ring and let Answering Machine pick up, there is a hang up

If I answer the call after 4 or 5 seconds it hangs up.

When I call the number back I get a busy signal.

I contacted MTS Operator and they patched me thru to MTS Security they advised for me initiate the Call Trace Feature;

The following must be done immediately after that call from the number that you want to have traced.

From an MTS Landline.

Dial *57

Press 1 to initiate and report the last number that called

Do this 6 or 7 times for the same number you wish traced, then call MTS Security or the Police for further Action

the number belongs to CPAR - Canadian Physicians for Aid and Relief

yet another unwanted call from them.

same as previos reports- no one there

This number has been calling me lately.. if you answer there is never anyone there. If you call back they give a message we are experiencing difficulties and call back in 48 hrs.  Seems like a scam of some kind.