The lead in the first story was simply that there was a fire, where it was, if anyone was injured, and what they were doing to control it. It was just the hard facts. The lead in the updated story was the cause of the fire.
The main news in the first story is again, the straight facts. The first story was being written as the fire was taking place so it told immediately that two firefighters were injured and talking about how firefighters had to fight the fire from the outside. It also talked about the current condition of the fire.
The second story elaborated on what happened. It explained things, it gave witness accounts, and it gave quotes from people affected by the fire.
The second news story was simply a change from the original story.