SALISBURY, N.C. -- Firefighters arrived for Victor Isler's viewing at a Salisbury funeral home in the same fire trucks they took, with sirens blaring, to the mill fire last Friday that claimed his life.

Joseph Burris made the trip on Wednesday from eastern North Carolina. He trained Salisbury firefighters in fire and rescue after September 11, 2001, and said he feels a special bond to the firefighters in mourning. Burris said it's especially strong because 40-year-old Isler was an emergency responder in New York on 9-11.

"I'm here to show support because we are a brotherhood, and we need to support each other when this occurs," he said.

And while long lines of Isler's friends stretched across the parking lot, just several blocks away agents with the Bureau of Alcohol, Tobacco and Firearms continued digging through debris at Salisbury Millwork. They’re looking for clues to help them figure out what caused the fire that killed Isler and 19-year-old firefighter Justin Monroe.

Earl Woodham, an ATF supervisor, said his crew also worked the tragedy in Charleston when nine firefighters died last June. He said he sees many similarities.

"The devastation is obvious. Fire is devastating; realistically it looks just like what happened in Charleston. Unfortunately results were similar," he said.

Woodham wouldn't say exactly when he'd release a cause, but he did say it would probably be in the very near future. Burris hopes when the investigation wraps up and the firefighters are laid to rest, it ends a deadly year for firefighters in the Carolinas.

"It's occurring with alarming frequency, and we're hoping that we don't have to come back to more of these on-duty deaths," he said.

The visitation for Monroe is scheduled for Wednesday night at the Miller’s Ferry Fire Department in Salisbury.

The funeral for both Isler and Monroe will be held Thursday at 2 p.m. at the chapel at Catawba College. You can watch it live on Channel 9 or on WSOCTV.com.