Make use of the article to answer the questions.

(CNN)The arduous search for a missing technology executive and five others feared dead after a suspicious fire destroyed a mansion in Annapolis, Maryland, could take days, fire officials said Tuesday.

The 16,000-square-foot waterfront house belonged to executive Don Pyle, chief operating officer for ScienceLogic, company spokesman Antonio Piraino said.

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."

1. Who owned the house?
2. What type of house is it?
3. How large is it?
4. Did it have a cellar?
5. Did it have an attic?
6. Who else lived in the house?
7. How many days had passed since the fire?
8. Had they begun to search the house yet?
9. Why?
10. Any other reason?
11. Who was heading the search?
12. What's his rank?
13. What state was the house located in?
14. What county?
15. Had anyone gotten any communications from Pyle?
16. Who is ScienceLogic's representative?
17. Who is the COO?
18. What was his wife Sandy's occupation?
19. How many are thought to be dead?
1. Don Pyle
2. Waterfront
3. 16,000-square-foot
4. Yes
5. unknown
6. Pyle's wife and four grandchildren
7. unknown
8. No
9. Parts were still burning
10. Waiting for equipment
11. Robert Howarth
12. Captain
13. Maryland
14. Anne Arundel
15. No
16. Antonio Piraino
17. Don Pyle
18. unknown
19. Six