Some exciting stuff and a classic scenario, reminiscent of the great scene from Goldfinger. You really need to pick one tense and stick with it. The mix of present and past is very distracting. You’ve got some other grammar stuff that could use some work as well, like verb/subject agreement. It’s nit-picky I know, but all the technical stuff has robbed your story of most of its effect and power.
THX 0477