A train carrying chemicals derailed early Tuesday, leading emergency officials to evacuate dozens of homes within a half mile of the site, officials said.

Tennessee Emergency Management Agency spokesman Donnie Smith said about 20 cars left the track but no chemicals had leaked and no injuries were reported.

The train's cargo included liquid propane, carbon dioxide, the polymer methyl ethyl acrylate and the chemical propylene oxide, which is used to make polyurethane, flame retardants and synthetic lubricants.

"This kind of stuff is poisonous to breathe," Smith said.

Smith said 65 people had been voluntarily evacuated from the area as a precaution.

The cause of the derailment is under investigation.