Comment by _aleph2c_

Here is an article about how the ammonium nitrate ended up there in the first place:

https://www.aljazeera.com/news/2020/08/05/beirut-blast-traci...

Here is an article about the history of ammonium nitrate:

https://www.nationalgeographic.com/science/2020/08/deadly-hi...

(comment edited)