This 400-pound, sidewalk-roaming security robot just got fired

A five-foot tall, 400-pound robot with four surveillance cameras just got fired from its security job. Right before Christmas.

The San Francisco animal welfare non-profit, SF SPCA, rented the 'bot to roam its parking lot and grounds, ostensibly in response to a recent burglary.  But to the dismay of neighbors, the SPCA also let the robot patrol the public sidewalk outside the property. 

Now, after being sent a deluge of threats, Ars Technica reports the SPCA has pulled the plug on its robot... for now.