HCNN - VIDEO | Alabama Train Derailment: Norfolk Southern train derails hours before CEO testifies

A Norfolk Southern train derailed Thursday in Calhoun County, Alabama, hours before company CEO Alan Shaw faced lawmakers to answer questions about a derailment on February 3rd that led to a toxic chemical spill in East Palestine, Ohio.

It's not clear what caused the derailment. A company's spokesperson said they are working closely with local officials.

This is the third derailment of the company's trains since last month. Over the weekend, 28 cars derailed in Springfield, Ohio.