1. A surveillance system comprising: a first sensor apparatus adapted to transmit toward and receive from a subject in a subject position, first electromagnetic radiation in a frequency range of about 100 MHz to about 2 THz, from positions spaced from the subject position, the subject including at least a portion of a person in a subject position and detectable objects carried by the person, the first sensor apparatus producing from the received radiation, a first image signal representative of a first image of at least a portion of the subject; a second sensor apparatus different than the first sensor apparatus, and adapted to detect a given characteristic of an object potentially carried by a person in the subject position; and a controller adapted to control operation of the first and second sensor apparatus, and to produce, from the image signal, image data representative of the image of the at least a portion of the subject, and relational information about whether the person is carrying an object having the given characteristic.