Device and method for detecting opening of or an attempt to open a closed container

A system, comprising:

• a closed container including two portions and having a slot extending between said two portions;
• a first electrically conductive wire that extends across the slot;
• a near field communications circuit having first terminals connected to an antenna and second terminals connected to ends of the first electrically conductive wire;
• and
• a conductive element that is electrically connected to one of the first terminals and positioned adjacent to the first electrically conductive wire;
• wherein said near field communications circuit is configured to:
• apply a voltage across the first electrically conductive wire;
• sense a voltage at one end of the first electrically conductive wire;
• generate a signal indicating a tampering state of the closed container in response to the sensed voltage, the sensed voltage having a first voltage value if the first electrically conductive wire has been severed by tampering;
• sense a repairing of the first electrically conductive wire which short circuits the repaired first electrically conductive wire to said conductive element;
• and
• reporting the tampering state using a near field communication over said antenna;
• and
• wherein operation of the near field communications circuit is blocked in response to sensing the repairing of the first electrically conductive wire.