Tamper detection apparatus for an electric meter (M) installed at a facility supplied power through an electrical distribution system, the meter being connected to the facility using a receptacle (K) and monitoring electricity usage at the facility for electricity delivered to the facility flowing through the meter. A sensor (RR) senses movement of the meter more than a predetermined amount with respect to the receptacle, whether or not electricity is flowing through the meter, and produces a tampering signal when this occurs. A second and optional sensor (Z) senses the proximity of the meter to its receptacle with removal of meter from its receptacle producing a tampering signal representative thereof. Generation of a tampering signal results in a tamper alert signal being transmitted to the system through a two-way communications path established between the facility and the system.