No one was injured by the gunfire but things could have been different had the semi-automatic handgun not jammed.
The incident happened around 6 p.m. Saturday and afterward, the Southlake Mall in Hobart was evacuated and closed for the rest of the night.
A witness photo shows the three suspects sprawled on the ground in handcuffs moments after the shot was fired.
It happened on the first floor in the bustling center of the mall.
"I just heard a very loud noise," said mall employee Katie Hancock. "I thought something had fallen, maybe a sign in the mall or something. But then someone said it was a gunshot, so we got to the back."
It began, police say, with an argument about a basketball game that had been played earlier.
One of the teens pulled a gun and fired a single bullet in the air.
Police say the semi-automatic handgun then jammed, preventing more shots from being fired.
"Officers went downstairs and apprehended the suspects while they were running through the mall and located the weapon," said Hobart Police Sgt. Jeremy Odgen.
No one was hit by the bullet, which lodged in the floor above, and one teen who was not arrested suffered minor injuries in the fight.
Southlake Mall was immediately shut down and shoppers were told to evacuate.
"The security officers of the mall just told us to have people go out our back door, to show them out through the employee hallway, and get people out," Hancock said.
"Everyone was trying to find the way to get out of the mall but we couldn't find it because on the main floor there it's hard to find the exits," said witness identified as Leanna.
The shooting occurred as retailers are gearing up for the busy holiday shopping season.
Hobart police have a message for shoppers.
"It's going to be safe," Sgt. Ogden said. "There's good officer presence here. I think it was very important that during this time of something bad happening here at the mall, there's three officers just above where it occurred."
Police said all three suspects are under the age of 18, their names have not been made public.