CUSTER, WA (MyBellinghamNow.com) – The cause of a recent train derailment near Custer has been determined.

The Federal Railroad Administration (FRA) says preliminary reports suggest that the train had traveled through a previously run-through switch during the incident. The FRA also says the previous train appeared to have left a gap in the switch points, which caused six of the 26 cars on the following train to derail on the evening of June 4.

BNSF says no injuries were reported and there was no damage to its main line.

The FRA says it is not formally investigating the derailment because it doesn’t meet their criteria for doing so.

BNSF still has to write its own report on the incident, which will be released in about three months.