This has been tracked since it loaded and left China.  “Shipload of Rocket Fuel Arrives in Iran,” Maritime Executive, 3-30-25.  “The Jairan has been linked to Iran’s procurement of sodium perchlorate, a chemical used in solid rocket fuel” for missiles.

“Iran Has Rejected Direct Negotiations With the U.S. in Response to Trump’s Letter,” Time, 3-30-25.

“Iran ‘threatens to target UK forces in Chagos Islands if Trump launches attack’,” The Standard, 3-30-25.

As the article points out, this is “part of more than a decade of violent plots targeting its critics abroad.”  See “How journalist Masih Alinejad survived multiple assassination plots by Iran,” PBS, 3-30-25.