A simulated battlefield mine (1) for an electronic shooting game provides improved visual effects and new challenges for players. A flash beacon (10) is operated to flash repeatedly to provide a warning before a simulated mine explosion. In a vulnerable mode of operation the mine (1) may be hit by radiation from a shooting game gun as recorded at a sensor/transmitter unit (11). This may delay or prevent an explosion occurring. When an explosion occurs, strobe lights (9) are operated in a flashing mode, a siren (16) is activated, and a speaker (15) emits a sound simulating an explosion. At the same time, radiation is transmitted from the units (11) to hit players who are in the line of radiation. Many variations in the mode of operation are possible under computer (3) control.