I Actually really like idea, just not sure how make it work in the script. I would have to find all people within a radius(thats easy enough) and making them stop or maybe walking a bit further away (thats proberly also possible). But the problem would be after the incident. Then you would have 20-30 people standing on the map not moving anywhere and most likely standing in the middle of the road causing problems
Can't the peds stay to a designated path?