SUPERIOR, Wis. (AP) — Authorities say an explosion and fire at a Superior oil refinery poses no danger to the public.

Superior Fire Chief Steve Panger says the explosion happened in an empty asphalt tank at the Calumet Oil Refinery just before 3:30 p.m. Tuesday, and the fire was contained to that tank. The fire burned residual material in the 30-foot-wide tank.

READ MORE: 'It’s Just Heartbreaking': Prayer And Grief Highlight Vigil For Eli Hart

WDIO-TV reports the fire sent a plume of smoke that could be seen from nearby Duluth, Minnesota.

No one was hurt.

READ MORE: Home Team: The Storied Career Of 82-Year-Old Umpire Bill Peterson

The city’s three engine companies responded. Panger says Calumet activated its emergency response team and evacuated non-essential personnel.

Calumet says the cause of the fire has not been determined. The company says production at the refinery has not been affected and that regulatory agencies have been notified.

MORE NEWS: Man Cited After Being Caught Sunbathing Atop Elementary School Roof

(© Copyright 2015 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)