Eight people who were injured in a fiery explosion at a Searsmont sawmill were still hospitalized Monday, while three firefighters and a mill employee have returned home.

Officials have now identified the 12 people injured in Friday’s silo explosion at Robbins Lumber in Waldo County, which drew a massive response from first responders.

Andrew Cross, 27, a member of the Morrill Volunteer Fire Department, was killed in the fire and blast.

Three members of the Robbins family — co-owners Jim and Alden Robbins, as well as family member Lily Robbins — were injured in the incident and are being treated in a burn unit at Massachusetts General Hospital, according to statements from the company.

Jim Robbins is president of the company, and Alden Robbins is the vice president of sales, according to the company. Lily Robbins is Alden Robbins’ daughter and an EMS volunteer.

“They have a long road to recovery ahead, but they are in the very best hands, and we look forward to their return,” co-owner Catherine Robbins-Halsted wrote in a statement on the company’s website.

Massachusetts General Hospital spokesperson Timothy Sullivan confirmed Monday that three people remained in critical condition at the Boston hospital.

Five patients who were injured in the fire are still being treated at Maine Medical Center in Portland, a spokesperson said Monday afternoon. Two patients have been treated and released, while one person was treated and transferred to another facility, according to a spokesperson, who would not identify that facility.

The Office of the State Fire Marshal on Monday released the names of the people injured in the incident and provided an update on the investigation.

According to state fire officials, Searsmont fire Chief James Ames has been released from the hospital, and Assistant Chief Wayne Woodbury is being treated at Maine Medical Center.

Searsmont EMS Chief Sarah Tompkins, Montville firefighter Jacob Spaulding and Belmont firefighter Katherine Paige are also being treated at Maine Med.

Appleton fire Chief Clifton Marriner was treated and released, as was Lincolnville firefighter Aaron Heald.

Mill employee Thomas Wolf is also at Maine Med, while John Ward has been released, according to state fire officials.

MULTIPLE INVESTIGATIONS UNDERWAY

The explosion is under investigation by multiple federal agencies and the state fire marshal’s office.

The Bureau of Alcohol, Tobacco, Firearms and Explosives announced Monday that its agents will help state investigators determine the origin and cause of the fire.

A spokesperson for the Occupational Safety and Health Administration confirmed Monday that the agency has opened its own investigation into the matter.

State fire officials said the investigation at the scene has focused on documentation, evidence preservation, aerial mapping and witness interviews.

High winds have created difficult working conditions, particularly for drone operators and aerial photography, Department of Public Safety spokesperson Aaron Turcotte said. One ATF investigator sustained a minor injury because of the conditions, Turcotte said.

Investigators have conducted more than 50 interviews and expect to do “many more,” Turcotte said.

“Multiple interviews conducted during the last operational period continue to help investigators better understand the sequence of events surrounding the fire and subsequent explosion,” Turcotte said in a statement.

Turcotte said investigators have also been looking at similar mill infrastructure and electrical systems to better understand the Robbins facility layout and operations processes. Robbins Lumber has fully cooperated with the investigation, he said, and portions of the mill can operate safely without interfering with the investigation.

Robbins Lumber will remain closed for at least a week, company officials said in a statement.

FIREFIGHTERS FACE LONG RECOVERY

Spaulding, the Montville firefighter, faces “a long and challenging road to recovery,” according to a GoFundMe started by Sarah Brown, his girlfriend’s mother.

Brown wrote on the fundraising page that her daughter was at the scene of the fire and saw Spaulding emerge from the flames. She started to drive him to the hospital, and they were met on the way there by an ambulance.

Montville fire Chief John York said Monday that Spaulding is “doing OK” and called him a “good young man.”

“He’s been one of our staples, and now we’re just hoping he’ll be all right,” York said in a brief phone interview. “It’s going to take time. It will be a while getting better.”

York said he did not know how long Spaulding had been with the department and said he wasn’t up for talking more about the fire and explosion.

The Lincolnville Fire Department posted a short message and photos on Facebook on Sunday night welcoming home Heald, the injured firefighter. The photos show Heald, his hands heavily bandaged, posing in front of a fire truck that was draped with a hand-drawn banner that read, “Welcome Home Aaron.”

Heald’s family did not immediately respond to interview requests Monday.

Katherine Paige, the Belmont firefighter, is being treated for severe injuries, her husband, Paul, said Sunday. Her recovery is expected to take several months.

“She has a long way to go,” he said.

Paul Paige said in a Facebook post that his wife, who goes by Katie, was responding to his voice with nods and shrugs. He said she is still on a breathing tube and will need several surgeries and skin grafts.

She has served with the Belmont department for about a decade and also volunteers with the neighboring Northport Fire Department, her husband said.

Since the fire, community members have been collecting donations for those affected, including food, water and thousands of dollars.

Hammond Lumber Company announced Monday that it donated $100,000 to the nonprofit Maine Strong Memorial Foundation to be given to victims and families.

Editor’s note: This story was updated May 19 to correct the spelling of Searsmont EMS Chief Sarah Tompkins’ name.