MASON, Tenn. (AP) — Part of a CSX Corp. train carrying grain and carbon material derailed early Thursday in rural west Tennessee, but no injuries were reported and there was no danger to the public, officials said.

CSX said nine loaded cars derailed at about 4:20 a.m. in Mason, a small town about 40 miles northeast of Memphis.

The cars contained grain and carbon B material, officials said. Carbon B is a fine black powder used as a reinforcing agent in rubber compounds, such as tires, and as a black pigment in printing inks, surface coatings, paper and plastics, according to the U.S. Environmental Protection Agency.

Crews from various fire departments responded to the derailment, Covington Fire Chief Richard Griggs said.

Three cars partially ended up in a small creek, CSX said, and there were no injuries to the train crew.

CSX, Griggs and Tipton County emergency management director Tommy Dunavant said there was no hazardous materials threat.

The cause of the derailment was under investigation.