I don't really like the idea of putting a lot of photos of traumatized people on internet, photoshit happens, the last thing that those sons, women, family could merit is to be lynched on internet.
...but
If you know or suspect that the bags were black, a reasonable solution that maybe could have success without to blow up all the remains of privacy could be:
1-to create a filter that makes a copy of the originals AND change all colors of the bunch of photos in a named directory to i.e. soft blue... EXCEPT a small range of black tones.
2- Thus, you could check or search then in the bunch with another script what photos have those suspicious black tones. And you could choose to move those photos to a different dir for a preliminary analysis, maybe saving a lot of time.
2- or you could search for photos taken from same place in different times (very frequent in a competition) that have black tones NOT changing of place in a specific time. People moves, claps, node, etc, bags with bombs don't.
3-You could refine the script to permit to enter any desired tone also and mask all the other colors. The goal is to find quickly a bag, but keep the privacy of innocent people and victims that do not deserve this.
I thing that should not be much challenging technically.