Afraid I haven't been writing updates as we've been busy exploring the data. Our team decided to focus on the 2014 homicide data for Cartagena because it had geo-coded data already.
We cleaned the data a bit, in particular to get the hour of the day the homicide took place. We then used CartoDB to create a heatmap animated by the hour of the day. We found that interestingly, between 6-9pm there is a peak in homicides near a market that is closing at that time. Our visualisation is below.