It was an unforgettable scene, and a tragedy the Honolulu Fire Department is learning from.

The deadly blaze at the Marco Polo building is the biggest and most complex fire the department has fought in decades.

It’s been nearly two weeks since flames tore through the high-rise, leaving three people dead.

Over 120 firefighters fought the fire on July 14, or about one third of the department’s manpower on the island.

The Honolulu Fire Department initially reported a 5-alarm fire, however an after-action review made HFD realize the blaze actually reached seven alarms.

The department looked over data from that day and realized the emergency response was bigger than they thought. Fifteen fire engines and six aerial ladder trucks were used.

Fire officials say they don’t have all the answers yet, including what caused the deadly fire, but they have a clearer understanding of how rescue operations went.

On Thursday, firefighters gathered to review how they handled the fire, and listened to clips of communications that day between battalion chief Ken Lee and his firefighters.

“There was no question, a fire of this magnitude, there’s a lot of communication,” said Bobby Lee, president of the Hawaii Fire Fighters Association. “I was impressed listening to the battalion chief’s communication. (It) was very clear and easy to understand.”

Firefighters rescued five people trapped in their apartments on the 26th floor, which was where the fire started. One person was rescued on the 27th floor.

That doesn’t include the dozens still in the building who were brought to safety.

“We’re happy with the performance of the firefighters at the individual command and incident command level,” said Capt. David Jenkins, Honolulu Fire Department public information officer.

The fire, which spread quickly through the top floors of the high-rise, took hours to finally bring under control. A mobile command center, a vehicle meant for emergency operations, wasn’t used that day.

“It was dispatched, but it was not at scene and as far as further details about the mobile command center, that can be discussed at another time,” Jenkins said.

Overall, fire officials say they continue to study how they handled the Marco Polo Building blaze to see what can be done better.

“It’s going to have a lot of effect on City and County of Honolulu for a long time. Hopefully, there will be more efforts on fire prevention,” Jenkins said.

As for how the fire started, investigators have ruled out some possible causes, but officials will not release the information as they’re still actively investigating.