[St_Thomas_Aquinas]

I’ve never used a pressure cooker, but those backpacks don’t seem to be full enough to have one inside.

Neither pack looks like the black bag that we've all seen.

[AppyPappy]

If that black bag had a bomb in it, it would have been blown to bits, not shredded.

[expat2]

Not surprising. The backpacks used would be turned into small shreds by the explosion and shrapnel.