PHOENIX – Railroad ties caught fire in a Phoenix train yard Wednesday night, creating a visibly bright orange blaze and sending up smoke dense enough to shut down a freeway.

There were no injuries reported, the Phoenix Fire Department said in an email.

Crews arrived at the Burlington Northern Santa Fe Railway site near 19th Avenue and McDowell Road around 9:30 p.m. to find a large pile of rail supports burning.

There was so much smoke, authorities shut down Interstate 10 at Seventh Avenue in both directions.

The roadway was closed for two hours while firefighters tackled the blaze.

Crews went on the defensive and also had to handle the fire as a hazardous material battle because of rail cars next to the burning ties.

Firefighters stayed early into the morning to watch for hotspots.

Cause of the fire is under investigation.

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