MINNEAPOLIS (WCCO) – Crews are still working to snuff out the hot pockets left over after a paper mill sustained an explosion earlier this week.

Patti Gartland, a Sartell city administrator, said Thursday afternoon that the fire remains 99 percent contained; but as crews move collapsed parts of the mill’s warehouse, oxygen gushes in and fires flare up in the still smoldering paper bales.

READ MORE: Vikings Reportedly Hire Kwesi Adofo-Mensah As GM

Gartland said such flare ups were anticipated and are being extinguished as expected.

READ MORE: Supreme Court Justice Stephen Breyer Plans To Retire (CBS News)

The mill sustained a massive explosion, which killed one worker, Monday afternoon.

Close to 12 fire departments were on the scene Thursday. Another eight or so departments are expected to help put down the remaining embers Friday, Gartland said.

MORE NEWS: COVID In Minnesota: Average Positivity Rate Dips, 52 Deaths Reported

Authorities hope the firefighter will end Friday afternoon.