Just got a call from this number too looking for someone that wasn't here at the time. Person gave their name and refused to say who they were associated with or why they were calling.
I just received a call as well and although there was no message I could other agents in the background yapping about some promotion. Call number now blocked! :-)
Someone just called my place of business looking for the clinic manager, saying he was from the humane society, I told him he was not available, and he said he would call back another time.