Since we're assuming you can run the required distances, the key issue then becomes how to reduce recovery times between sprints so you'll always be prepared for the next one.
The way the US Army prepares recruits for it's Physical Fitness Test (I'm not saying it's the best method but it's the one I know) is to repeat max. efforts two days in a row.
For example, if your training for a two mile run, your timed your best effort one day, then have to give it your best effort then next day as well. You then begin your training interval again and are re-tested on the two consecutive days. The same thing is done for push-ups, sit-ups, etc.
The important idea behind this training is that soldiers need to perform at high levels, for varying times and under adverse conditions. I imagine this is the idea behind the Police Fitness Test as well.
HIIT is close to the mark in that you're sprinting and then pacing yourself for random times. It might be worthwhile to add in 2 max effort sprints in a row somewhere and then repeat the process.
I should add that I'm not a sprinter myself. I thought that this idea might be useful in this situation.