SEARSMONT — On the same day funeral arrangements were announced for a firefighter killed in a fiery explosion last week, state and local officials provided an update on the investigation into its cause but offered few new details.

At a news conference Tuesday afternoon, Shawn Esler, the state’s fire marshal, described the investigation as “very active and complex,” but neither he nor assistant fire marshal Joel Davis offered a specific timeline for when it might be completed.

Earlier in the day, family members of 27-year-old Andrew Cross, who died from injuries he sustained in the explosion, said he’ll be honored at a public visitation on Thursday and a memorial service Friday.

Cross was a volunteer firefighter in Morrill and one of hundreds who responded to Searsmont on Friday for a silo fire at Robbins Lumber, a major Waldo County employer.

Federal and state authorities are still investigating the cause and origin of the fire and subsequent explosion, but Esler said Tuesday that removing Cross’ remains from the site of the fire was one of their “main focuses” in the immediate aftermath of the blaze.

Video shared by Liberty Fire & Rescue showed Cross being carried out of the site Friday afternoon in a flag-draped casket, flanked by lines of saluting first responders.

“Over the last several days, we have seen the very best of Maine,” Esler said. “Waldo Strong is more than a phrase, it is something you can feel.”

Twelve others — including first responders and mill staff — were injured. Eight of them remained hospitalized as of Tuesday morning, according to spokespeople for hospitals in Portland and Boston.

Many of those injured were still “fighting for their lives,” Esler said.

Robbins Lumber has not reopened but its owners have said they will rebuild, and the surrounding community has offered unwavering support.

INVESTIGATION ‘ACTIVE AND COMPLEX’

Federal and state investigators have been poring over details about the Searsmont sawmill fire since Friday evening.

Dozens of interviews have been conducted to determine how the fire started, officials said. The federal Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Maine Department of Public Safety set up a command post inside Searsmont’s town office on Saturday, and about a dozen people were still working there Tuesday.

But the fire’s precise cause remains undetermined. At Tuesday’s news conference, officials declined to provide a timeline or answer specific questions about the emergency response.

“We’re hoping to have it wrapped up in days, but wherever it leads us, we’ll take it from there,” Davis said.

Twenty-five fire departments from across the Midcoast region, most of which are made entirely of volunteers, responded initially, and Esler said an additional 21 local fire departments aided with the dayslong recovery and cleanup efforts.

It was a reminder of how much of the state is served by volunteers.

Most firefighters in Waldo County — and 69% statewide — are volunteers, according to Ken Desmond, president of the Maine State Federation of Firefighters, which represents volunteer firefighters across the state.

“The volunteer fire service needs help,” Esler said. “If you’ve ever considered volunteering, now is the time. Communities like Searsmont depend on it.”

Investigators’ initial scene examinations on Sunday were hampered by high winds that kicked up debris from the blaze. An ATF agent was cut by a piece of metal that became airborne, the agency said.

But as the winds died down and the temperatures rose Monday, efforts resumed. Heavy construction trucks and large cranes were being brought to the site to remove debris, according to Davis. Drones and computer mapping equipment will also be used in the investigation, he said.

“There’s obviously been other incidents at grain places and stuff like that, but this is going to be a new one at a lumber mill,” he said, referring to similar explosions that have occurred at agricultural grain silos. “We’re going to try to get some answers on that.”

REMEMBERING A HERO

Belfast-based Riposta Funeral Home will host a public visitation for Cross from 5-8 p.m. Thursday. A memorial service will be held Friday at 1 p.m. at Veracity Chapel in Morrill, according to an obituary published by the funeral home.

Gov. Janet Mills on Tuesday ordered the United States and Maine flags be lowered across the state on Friday in honor of Cross. They will already be lowered on Thursday in honor of civil rights leader Gerald Talbot and Maine Game Warden Joshua Tibbetts, who both recently died as well.

“My heart goes out to the family, friends and colleagues of Andrew Cross,” Mills said in a statement. “He died a hero.”

Cross’ friends have described him as a “wicked happy guy” with a big smile who was quick to help others. Morrill fire Chief Dean Rowlands said Cross “didn’t think twice” when responding to the massive fire at the lumber mill.

Cross also worked as a machinist at Bath Iron Works and as a landscaper who plowed the town’s roads. He enjoyed spending time hunting, fishing and snowmobiling, as well as visiting camp in Bingham and at Madagascal Pond in Burlington, according to his obituary.

“Although gone from this earth too early, Andrew’s spirit will forever be with us when we see a big buck, chase a fast rabbit, hear the soft tread of a bear, sneak up on a gobbling turkey, wet a line with a new lure, and hear the rumble of an old tractor or dump truck,” the obituary reads.

Desmond, with the volunteer firefighters federation, said he met Cross a few years ago while testing water pumps at Robbins Lumber. He recalled that the Morrill firefighter was interested in learning how the equipment worked and described him as an overall “happy-go-lucky” man.

“He’ll drop anything to help anybody out,” Desmond said. “That’s the kind of character Andrew was.”