A freight train derailed in the US state of Oklahoma Friday, sending at least 20 railcars off the track, though didn't cause any injuries, local media reported. The derailment happened in Tulsa in northeast Oklahoma early Friday morning when a Burlington Northern Santa Fe train ran into the back of some cars that had come uncoupled from another train, the website of newson6.com reported. No injuries were reported in the incident. A diesel fuel leak was contained shortly after responders arrived at the scene. The diesel fuel was coming from a train engine, and the fire department said it did get into a nearby creek. Tulsa Fire Department spokesman Stan May told the media none of the cars contained hazardous materials. May said the train was hauling new automobiles, food products and other items. Crews were using heavy equipment to clean up the debris left from the derailment, including the rail cars. The derailment caused delays in the morning commute because several railroad crossings were closed. Burlington National Santa Fe officials said the railway is investigating the incident as an act of vandalism. The FBI has also been called in to investigate it.