Marines and police officers with Security Battalion conduct their final active shooter training for 2013 at combat town aboard Marine Corps Base Quantico on Nov. 20, 2013. The exercise was conducted with the help of simulation rounds, stationary and moving targets. The moving targets were volunteers from Combat Camera, this proved a more realistic scenario for the shooters. - Marines and police officers with Security Battalion conduct their final active shooter training for 2013 at combat town aboard Marine Corps Base Quantico on Nov. 20, 2013. The exercise was conducted with the help of simulation rounds, stationary and moving targets. The moving targets were volunteers from Combat Camera, this proved a more realistic scenario for the shooters.