A system comprising: at least one processor; at least one sensor; and computer executable instructions readable by the at least one processor and operative to: use the at least one sensor to determine a number of persons or identity of a person; and trigger an alarm based on the number of persons or the identity of the person. A method comprising: using at least one processor to perform any or all of the following: use at least one sensor to determine a number of persons or identity of a person; and triggering an alarm based on the number of persons or the identity of the person.