Ariana took to Twitter a few hours after the incident, writing, "Broken. From the bottom of my heart, I am so so sorry."
The devastated singer then cancelled all upcoming shows and went home to be with her family.
Her drummer, Aaron Spears, took to Instagram to describe how the event unfolded, writing, "We finished the show and were walking back to our dressing rooms and BOOM!!!! We could hear people panicking... We had no idea what was happening."
"There was all kinds of speculation as to what was going on," he said. Before saying that security quickly came into the room, telling the band they had to evacuate the building immediately.
"It was then that we realised that this was serious."
"It's so heartbreaking because so many little ones attend our shows...I just keep thinking about them," he wrote.
"I'm extremely thankful that no one on the touring crew was physically hurt but this painful memory and the weight associated with the lives lost will live with us all forever...I'm still just in disbelief....It's so surreal."
This article originally appeared on marie claire.