Updated: January 29, 2014 at 7:30 pm
CHICAGO (AP) — An increase in rail shipments of oil crude from the northern Plains is being partly blamed for disruptions to an Amtrak route linking Chicago and the West Coast.
The National Association of Railroad Passengers wrote to U.S. Transportation Secretary Anthony Foxx this week urging him to intervene.
Amtrak's Empire Builder service runs along a BNSF Railway route that has seen an increase in oil shipments from the Bakken region of North Dakota and Montana.
Winter weather has exacerbated several months of disruptions. Westbound Amtrak trains this week have had to bypass stops across much of North Dakota. Delays have reached up to 10 hours.
Amtrak spokesman Marc Magliari says Fort Worth, Texas-based BNSF has said disruptions could continue for months.