TULSA, Oklahoma - Railroad crews are on the scene of a train derailment in Downtown Tulsa, and the stretch of tracks in downtown Tulsa is still closed. BNSF said they're not sure how long it'll take to reopen the railroad.

The cars slipped off the track then three of them flipped over near Greenwood and Archer.

Railroad workers are on scene trying to determine what caused the derailment.

They said no one was hurt.

We talked to a man who says he saw the derailment from his office. Te said the train started wobbling about 40 yards before it went off the track.

"I just walked upstairs to talk to my boss and looked out at it and one of my coworkers saw the smoke first and we all looked and there it went," one witness said. 

BNSF says the train is owned by Stillwater Central Railroad.