SUPERIOR, Wis. -- Mayor Jim Paine has lifted the evacuation order for Superior residents living near the Husky Energy oil refinery, which was rocked by a series of explosions and fires Thursday, April 26, and sent a black plume across the city.

"People can comfortably go to their own homes," a press release from the City of Superior sent shortly after 6 a.m.  Friday said. "Thank you for your patience and cooperation while we dealt with this very unfortunate situation."

Essentia Health and St. Luke’s hospital officials said a combined 11 refinery victims were confirmed treated in Duluth and Superior facilities, one with a “serious blast injury.”

No fatalities were reported, and all employees and hundreds of contractors working at the refinery were accounted for.

No details were available on the extent of refinery damage or what caused the initial explosion that occurred just after 10 a.m., apparently in a tower near giant asphalt storage tanks. One of those tanks was punctured, spewing liquid asphalt onto the ground for hours.

A second, larger fire erupted just after noon with multiple explosions throughout the afternoon, sending a much bigger black cloud billowing for miles.

Kollin Schade, refinery manager for Husky, told reporters that the facility was preparing for a May shutdown for servicing and inspection at the time of the explosion and that most of the fire and smoke was from asphalt burning.