PARLAND, Fla - As students in Parkland, Florida prepare to head back to school after a Valentine’s Day massacre on campus.
New questions are emerging about the actions of some deputies at the Broward County Sheriff's Office, in how they responded as the active shooting unfolded.
As officers from local police departments rushed to the shooting at Stoneman Douglas High, sources say three Broward Sheriff's deputies remained outside the freshman building where most of the shooting took place.
It is not clear why.
The sheriff's office did not respond to NBC News on a request for comment.
"When we look at this type of tragedy and this type of incident and realize that there were people in place that might have had a way to prevent this and then people that at the scene didn't do all they could, it's just heartbreaking and uh I’m angry. I’ve gone beyond sorrow and I’m angry and I think we need answers," said Michael Udine, a commissioner for Broward County.
The new revelation comes just days after Broward Sheriff Scott Israel announced the school's armed guard did not go into the school building either.
"What matters is we in law enforcement arrive at an active shooter, we go in and address the target and that's what should have been done," Israel said.
NBC News terrorism analyst Clint Van Zandt says it's a lesson learned from previous mass shootings.
"We learned that terrible lesson in Columbine that you cannot wait, that is your job is to run toward danger in this particular case, because if you can't isolate, if you can't neutralize that shooter, every second there is a chance people are dying," Zandt said.
For the students who survived added concern about their safety.
"It shows me the terrifying reality that we live in this country -- to the point that police officers that are veterans are not willing to go in and take out an individual with an AR-15., but that's when you know there's something seriously wrong,” said David Hogg, a student from Marjory Stoneman Douglas High School.