By ANAEL GAVIZON

Last Sunday, there was a mass shooting in Las Vegas during Jason Aldean’s concert performance. A lone gunman unleashed bullets from the 32nd floor of Mandala Bay Casino and Resort.

The shooter killed at least 58 people and injured more than 500 others attending a country music festival below, according to officials.

The initially unknown shooter, now identified as Stephen Craig Paddock, fired shot after shot from his room at the hotel down on the crowd of about 22,000.

Terrified concertgoers were literally running for their lives. It has been the deadliest mass shooting in modern U.S. history.

As one can see, this story was breaking news late on Sunday and early on Monday. However, most of the information was incomplete and unknown. It is a story that has been developing during the week. Each day adds new information that sometimes leads to new stories.

This is one of the challenges of covering breaking news. Sometimes you could get more information, details and sources than others.

The process begins with an alert that carries immediate, yet very limited information. That would be the first news on Sunday night. Next comes the news break, which includes the answer to main facts (who? what? when? where?), the source and the circumstances.This would be the stories from Monday and Tuesday talking about the details of the event, most importantly who committed the act and why.

Last, but not least, the updates and second stories that are stories carrying an earlier report by weaving together fresh developments, reactions, added context and analysis. These are stories like the ones about the gunman’s girlfriend, heroes that saved lives, interviews with the killer’s family.

Little by little, journalists get to weave the story, starting from the very basic and developing into the more complex details.