Twenty train cars went off the tracks around 4 a.m. today in Readfield as a Pan Am Railways train was en route from Hermon to East Deerfield, Mass.

No one was hurt and the cause is unknown, a spokeswoman for the railroad said this morning.

The 71-car train was carrying paper, lumber and scrap cars and was operated by a two-person crew. Pan Am, which is based in Massachusetts, is sending a team to investigate the accident.

A caller to the Kennebec Journal this morning said the derailment happened near Thorpe Shores Road, which is off South Road.