SCOTLAND, S.D. (AP) — Federal transportation investigators have begun interviewing the engineer and conductor of the train that was carrying the seven ethanol tanker cars that derailed in South Dakota over the weekend.

National Transportation Safety Board spokesman Terry Williams says the interviews began Monday morning. Seven investigators arrived at the scene Saturday night and examined the cars Sunday.

No one was hurt when the cars derailed Saturday morning, and at least one caught fire. The train was operated by BNSF. The railway has indicated the train carrying ethanol derailed about 6:15 a.m. over a small bridge that spans a dry creek, between the towns of Scotland and Lesterville.

Williams says a detailed incident report will take at least a year. Investigators will have access to the damaged tanker cars throughout the investigation.

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