A lumber mill in Maine exploded and burst into flames Friday – as authorities declared the terrifying situation a “mass casualty event.” 

At least 11 people – including multiple firefighters – have been injured and one is in critical condition after 911 received a call about an inferno at Robbins Lumber mill in Searsmont, about 90 miles from Portland, at about 10:05 a.m. 

“We have dumped all of the resources from the whole county over to that area,” Waldo County 911 director Mike Larrivee said Friday afternoon, according to local news outlet WMTW. 

Officials declared the incident a “mass casualty event” not because there were any deaths, but because there are believed to be more victims than local authorities are equipped to handle, the outlet reported. 

Nearby roads were reportedly closed as authorities urged residents to avoid the area. 

Horrifying photos and video footage show giant, thick plumes of smoke billowing from the blazing mill – where, miraculously, no employees were injured and all are accounted for, according to Catherine Robbins-Halsted, President of Robbins Lumber East Baldwin.

She said that typically two people work in the affected area. 

The fire, which caused significant structural damage to the sprawling facility, appeared to be contained about two hours after it began, Robbins-Halsted said, per WMTW.

But local reporter Jacob Murphy reported hearing additional explosions at the scene at 1:45 p.m., the outlet reported. 

A fire department chief from the nearby city of Augusta said that a member of their ambulance crew located one patient with burns sustained in the incident and transported them to a hospital in Augusta – as medical facilities in Searsmont were already busy with other patients. 

A second victim drove themselves to a hospital in Augusta, the chief reportedly said. 

Another patient in critical condition was reportedly being treated at Northern Light Eastern Maine Medical Center in Bangor before getting transported to another facility. 

A third victim – a 20-year-old firefighter from Lincolnville – was also being transported to Maine Medical Facility in Portland. 

That hospital was reportedly anticipating 10 patients from the mill explosion to be transferred to its Emergency Department Friday afternoon. 

The remaining victims’ injuries weren’t immediately known. 

The Thorndike Fire Department said that multiple firetrucks responding to the inferno have been burned, and several “maydays” have been called, WMTW reported. 

Flame-jumpers from nearby areas, including Camden and Thomaston, were sent to battle the blaze, at least one firefighting helicopter was dispatched, and the Maine Fire Marshall’s Office said it was sending investigators to the mill. 

The origin of the blast wasn’t immediately clear, and state Fire Marshal Shawn Esler said it would likely be quite some time before a cause was known. 

Ten trained responders from the state’s Red Cross disaster action team were also en route to the scene Friday afternoon. 

The Red Cross said it would serve in a supportive capacity, ensuring first responders have the resources – including water, food, blankets and cots – to continue fighting the fire. 

The investigation will also include officials from the Bureau of Alcohol, Tobacco and Firearms, the Occupational Safety and Health Administration and the Maine Department of Environmental Protection. 

Maine Governor Janet Mills, who was reportedly planning to visit the impacted area Friday evening, urged residents to “stay clear of the area, follow the instructions of law enforcement and allow emergency personnel to respond.

“I ask Maine people to join me in keeping all those affected in their thoughts,” she wrote in a statement. 

The mill – which is part of a family-owned business that’s been passed down five generations – is described as a “high-tech lumber manufacturer” with around 115 employees, and another 100 spread out at other locations across the state. 

The owner of the mill reportedly said it will be out of commission for at least the next week. 

It’s apparently a popular spot among Pine Tree State politicians, with Maine Sen. and governor hopeful Rick Bennett announcing policy plans from the mill just last week. 

In a statement about the explosion, Sen. Angus King said he’s “visited this mill frequently and my heart goes out to Jim Robbins and his family, the workers, and the Searsmont community.

“For your safety and the well-being of our wider Maine community, please follow the guidance of local emergency personnel,” he said. 

“The Robbins family is beloved in the Searsmont community, and Robbins Lumber is a piece of Maine history,” Sen. Susan Collins said in her own statement. 

“I have known the family for many years. My heart goes out to them, their employees, and the first responders who have come from all over the region to help in the emergency response. This is a very sad crisis, and all those affected are in my prayers,” she wrote.