Until 9-11 this was the largest single incident LODD's in the US. The web site Fire Service Line of Duty Deaths has an excellent article and videos under the "notes".
At least 581 people were killed, including the ENTIRE Texas City Fire Department, except for one man. Thousands were injured in the explosion of two ships loaded with ammonium nitrate. Good article in Wikipedia . . .
The LODD web site is from the Texas Department of Safety and is narrated by James Whitmore. Everything you could do wrong was done, everything that could happen did. 100 people were presumed dead because their remains were never found.