The 16,000-square-foot waterfront house belonged to executive Don Pyle, chief operating officer for ScienceLogic
, company spokesman Antonio Piraino
Pyle was believed to have been at home with his wife, Sandy, and four grandchildren.
The sheer size of the structure and the fact that three-fourths of the building had collapsed into the basement, with piles of deep-seeded debris still smoldering, compounded the search, said Anne Arundel County Fire Capt. Robert Howarth, who is leading the investigation along with a team from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.
"Your looking at five standard houses put together," he said. "This is more of commercial fire than it is a residential fire. There are a lot of businesses that aren't 16,000 square feet. That adds to it."
Pyle had not been heard from on Monday, and his colleagues at ScienceLogic were "hoping for a miracle," CNN affiliate WJLA-TV
in Washington reported.
By midday Tuesday, fire officials had not been able to search the still-burning ruins, Howarth said. Heavy equipment is being moved in over the next 12 hours to aid in the search for victims and clues -- a process that could take days.
"We have some very unique challenges with this house," Howarth said. "The construction of the house contained a lot of very heavy materials. We're looking at some steel beams that weigh in the area of 7 tons."
When the first firefighters arrived on the scene early Monday, they received conflicting reports about whether the family may have been out of town. But after interviews with relatives, it was determined that six members of the family were not accounted for, Anne Arundel County fire officials said.
"We still do not have 100% proof that they're in this house," Howarth said.
Fire officials said they were alerted to the fire about 3:30 a.m. Monday. About 80 firefighters responded.
The ATF national response team responded because the fire was deemed suspicious, Howarth said.
The burned-out home is being treated as a crime scene until investigators figure out the cause, he said.
The Anne Arundel County Fire Department said crews had difficulty knocking down the blaze because the house is secluded, apparently with no fire hydrants on the scene.
Photos the fire department posted on Twitter
showed hoses stretched for long distances. Capt. Russ Davies, Anne Arundel County fire spokesman, said it took hours for fire department tanker trucks and a fire boat on an adjacent creek to bring the fire under control.
Pyle's company bio described him as a industry veteran
who has held multiple CEO positions, with more than 25 years' experience in information technology infrastructure software and hardware management.
Pyle told The Washington Post last year
that after holding positions in a family business he decided to look for an "industry that was in its infancy and something that would have growth potential." He started in a sales position in a firm that connected computers over transmission lines, and later sold both hardware and software components for the Internet.
Pyle told the newspaper he eventually moved from sales to sales management to general management positions. In 1992, the company went public and was sold to Cisco Systems five years later for $4.2 billion, according to the Post.