One of the pictures shows a barbecue next to a burnt out house with the propane tank inside and it did not blow up.
It’s hard to blow up a propane tank...which is why explosives or detonators are usually required. This is built in, so that a brief but not explosive level high heat can’t do it.
It may be that somebody had left a wood or charcoal BBQ going and it tipped over. I don’t think it was intentional, it was just that these things happen and unfortunately the wind was so high that it took off from there.