Iran Bandar Abbas Port Explosion

[Big_Zukini]

April 26th 2025, a massive explosion occurred at the Shahid Rajaee Port near Bandar Abbas, by far Iran's largest sea port.
In 2020's Beirut explosion, said to be a large stockpile of Ammonium Nitrate, there was initially a gray smoke cloud and then an explosion containing a dark red smoke.
In yesterday's explosion in Iran, we see an orange cloud preceding an explosion containing a brighter red.

My main questions are:

1. What could this material be?
2. What are its typical uses?
3. Or in other words - is this something civilian or military in nature?

https://twitter.com/x/status/1916098353814802709

Port Shahid Rajaee location:

 

[publiusr]

It is tempting to think this was a military action—but even with weapon shipments—you can have accidents:

https://www.harpercollins.com/products/the-great-halifax-explosion-john-u-bacon?variant=32117355806754

Most powerful accidental non-nuclear man-made explosions in history – The Unwanted Blog

An interesting side note—at both Halifax and Texas City (1947)—a ship named “High Flyer” was present.

 

[Scott Kenny]

While I'm sure it's not the ONLY thing that would produce a giant plume of red-orange smoke, what comes to mind is Red Fuming Nitric Acid.

Which does have industrial uses (including as fertilizer components), but is also a rocket oxidizer.

Referring back to Doctor Lowe's How Not To Do It

This picture is from 2015 and represents a spill of about 2 tons of the stuff. Accident happened in Ukraine, but I chose this one for the very clear color.