An unwanted call from this invalid (i.e. spoofed) Fresno-area number arrived today.  When the answering machine picked up, the caller left no message, just dead space.  This is a favorite tactic of robocallers (unlawful telemarketers) who use automated dialers to place calls seeking gullible schmucks to rip off.

Stop these telecriminals at the point of contact!  Let your answering machine take their pathetic, thieving calls!