TULSA, Oklahoma - Firefighters are investigating a fire that involved about 20 units at an east Tulsa storage facility. They were called out to 9727 East 11th Street around midnight and spent several hours in the cold working to make sure the fire was completely out.

Heavy smoke was pouring out of the northwest side of the complex when firefighters arrived, according to Assistant Chief Stacy Belk.

"There's a firewall so many units down, so we started at that firewall and worked out way back towards the fire," he said.

Crews cut locks off each unit they suspected was involved and had to cut holes into some of the rolling overhead doors to get out all the flames. 

"There were reports of possible victims," Belk said. "We've done our primary and secondary search and have not found one at this time."

Firefighters did see a woman leaving the storage complex before the fire broke out, according to on-scene reports. The property manager said no one should be living in one of the units.

"They're investigating whether it was a renter coming out here late or whatever the case may be," the assistant chief said.

It took about 30 minutes to get the fire under control, but crews spent time pulling out boxes and other property from the storage units and spraying compressed air foam to make sure nothing would re-ignite.

Belk said they will be looking at surveillance video from the complex in their investigation to see how the fire started. It was a massive response from several firefighting districts with teams coming from different parts of town to relieve primary crews and maintain coverage throughout the city, he said.

A property representative at the scene said they will be contacting renters of the affected units. About 20 had fire damage and more will have smoke and water damage.