Jamie Guttenberg, a student at the school, was confirmed dead by local media.
Guttenberg was a student at Douglas High. She died in the shooting, according to local news channel WPLG news station reported.
Her parents, Fred and Jennifer Guttenberg, were reportedly notified of her death later on Wednesday evening.
Guttenberg's Facebook page has also been changed to a memorial page.
Her brother, Jesse, was also at the school, but survived.
Martin Duque, a 14-year-old freshman, also died.
Martin Duque, pictured on the right of the photo above, was confirmed dead by his brother early on Thursday morning.
Miguel Duque posted on Instagram, and said: "Words can not describe my pain. I love brother Martin you’ll be missed buddy. I know you’re in a better place."
Aaron Feis, a football coach, was shot while protecting a student from the shooter. Local media say he has since died.
Feis, an assistant football coach and security guard at the school, reportedly leapt in front of a student to protect her.
Feis graduated from Douglas High in 1999 and returned as a coach in 2002, according to the school football team's website.
Broward Sheriff Scott Israel said on Wednesday night that "a beloved football coach is dead," but did not mention Feis by name.
According to the Sun Sentinel, Feis' family was notified that he had died in the early hours of Thursday morning.
School Athletic Director Chris Hixon has been confirmed injured.
Hixon, Douglas High's 49-year-old athletic director, was shot on Wednesday, the Sun Sentinel reported.
Allen Held, Hixon's former colleague, called Hixon a "super human being, the kind of person who would do anything for anyone."
Student Ben Wikander was shot three times and taken for surgery at a nearby hospital.
Wikander, a senior at Douglas High, was shot three times, WPLG reported.
His parents used the "Find my iPhone" app and found his phone at a hospital in the area. They later learned that he was undergoing surgery there.
Chad Reidlinger, a family friend, posted a photo and said Wikander is "safe."
There is also concern for Gina Montalto, another student.
Gina Montalto, pictured on the right of the photo above, was caught up in the shooting.
It is not clear exactly what happened to her, but numerous condolences message were being posted on her relatives' Facebook pages.
Her aunt, Shawn Malone Reeder Sherlock, posted a photo with the caption: "My sweet niece — just last week! My world." It was later deleted.
Several people remain missing in the aftermath of the shooting. Local media has named some of them.
The family and friends of at least eight students have appealed for news on their whereabouts.
Meadow Pollack, an 18-year-old senior pictured above, was missing. As of Wednesday evening, her family was awaiting news of her whereabouts.
Her father, Andrew Pollack, told the Sun Sentinel: "Her phone, she don't answer. She would have picked up her phone by now.
"No one knows where she is. We're all sick over this and just praying."
Alyssa al Hadeff, a 15-year-old freshman, was also missing. Her grandmother, Vicky al Hadeff, told South Florida's WSVN news station she visited several hospitals in the area for the teen and was fearing the worst.
Parents veer between hope and anguish as they await word from teens missing since the #school shooting at Marjory Stoneman Douglas High in Parkland https://t.co/KPkgD79VGV
Photo: Meadow Pollack, with a relative, courtesy Pollack family pic.twitter.com/UbUQl0lHgX
— Linda Trischitta (@LindaTrischitta) February 15, 2018
These are the victims of the Florida high school shooting
Peter Wang, 15, was last seen wearing his ROTC uniform, his cousin Aaron Chen told the Miami Herald.
Joaquin Oliver was also at Douglas High around the time of the shooting, his sister Andrea Ghersi wrote on Facebook.
Luke Hoyer, a 15-year-old freshman, was also reported missing by the Miami Herald. As of Thursday morning, his parents were waiting at a Marriott hotel in Coral Springs, where students were transported after the shooting.