Much of the Hulen Mall in Fort Worth is now open after a fire Friday night sent panicked crowds running as heavy smoke poured from the building's second floor. The Macy's wing of the mall remains closed, Hulen Mall Security said.

The Fort Worth Fire Department was called to the mall around 7:15 p.m., where a fire resulted in flames that shattered a glass roof. The fire was brought under control by 8:10 p.m., Fort Worth FD said. Four stores suffered extensive water damage, officials said.

The cause of the fire was not immediately known. Officials said roof repairs had been done earlier in the day, but no confirmed link to the fire has been established.

Fort Worth FD said one person was taken to the hospital, but didn't disclose the cause. 

"There was an incredibly large fan mounted on one of our trucks that was brought in to help ventilate extremely large buildings just like this," Fort Worth FD said in a statement.

Witnesses described the scene as chaotic and frightening, with some initially fearing a violent attack.  

"And as soon as we heard the explosion, the rail on the second level, the whole glass just fell to the bottom floor and everybody started running, and we didn't know what was going on," witness Guadalupe Morales said Friday. "I thought it was like a shootout or something because it sounded like a bomb."

One store employee recalled the panic as people fled.

"We were just, like, minding our business folding clothes," employee Britney Bellfield said Friday. "And then I look in the window, I see people, like, just sprinting, like running down the hallway. Like, what is happening? Like, we have no idea. It was scary."

The cause of the fire is under investigation.