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For the group of college buddies spending a late-season weekend at a friend's beach house, the deck overlooking a canal was the center of their good times.

It was where they talked, listened to music and danced late into the night. But investigators fear the deck just two blocks from the beach may also have been the starting point of a fast-moving fire that killed seven people, including a group of high school friends who went off to college together.

"It sounded like they were having a good time. Unfortunately, the fire didn't show any mercy," said Terry Walden, whose 19-year-old daughter, Allison, died in the blaze. "They probably never woke up."

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The storm of fire and smoke — so daunting that firefighters radioed for backup before they even arrived at the scene — enveloped the home early Sunday, killing six students from the University of South Carolina and one from Clemson University. Six other South Carolina students in the house survived.

Classes went on as scheduled Monday at South Carolina's Columbia campus, but grief counselors were available for the 27,000 students. Clemson also offered counseling.

About 1,000 people gathered on campus Monday evening to hear words of consolation. "Please reach out to one another, don't let others suffer in silence," USC President Andrew Sorensen said.

About 90 miles from Columbia in Simpsonville, more than 100 people gathered at an elementary school to pray for the victims. Officials and other families have said a number of the students killed went to high school together in nearby Greenville.

The house's owner, whose daughter was hospitalized Monday because of conditions from smoke inhalation, said his family was "numb, shocked and confused."

"There are no words to describe what we've been going through," Chip Auman said at the Carolina Pines Regional Medical Center in Hartsville. "We are living a nightmare."

Katherine Auman, 18, was in stable but guarded condition, he said.

Anna Lee Rhea said her older brother, William, was among the dead — a devastating blow to their older brother, Andrew, who made it out of the house alive. "Everybody loved him. Everybody really misses him," she said in a brief telephone interview from the family's home in Florence, S.C. "You couldn't help but love him."

In an interview from Chagrin Falls, Ohio, Walden said his daughter picked USC for its warm weather and vibrant Greek life. Officials have said many of the dead were members of the Delta Delta Delta sorority and the Sigma Alpha Epsilon fraternity.

"It's an awful loss for someone that had a pretty good future in front of her," said Walden, 56.

Mayor Debbie Smith said Monday that investigators believe the fire was likely accidental and started in the rear of the house, either on or near the deck facing the canal on the west side of the house. That side of the residence appeared to be the most heavily damaged.

Investigators should be able to determine where the fire started, but may have trouble finding a specific cause, said Dr. Rolin Barrett, a consulting engineer with Raleigh-based Barrett Engineering who has been involved in almost 1,000 fire investigations.

"So many things are consumed in fire that you can't tell what they were like beforehand," he said. "If a cigarette did it, then the cigarette was probably consumed."

As authorities removed the bodies from the charred home, they found most of the victims in the home's five bedrooms. The only person on the top floor who survived did so by jumping out of a window and into the adjacent canal, said Ocean Isle Beach fire Chief Robert Yoho.

Investigators quizzed dozens of college students who filled several homes near the site of the disaster.

Rebecca Wood, the president of the Alpha Phi Omega service fraternity at the University of North Carolina, said police wanted to know if the college students were using a grill or a small outdoor fireplace called a chiminea. She told investigators she didn't see anyone using the chiminea, and all the grilling was done far from the house.

Police in the beachfront community, which has only about 500 full-time residents, are working with the State Bureau of Investigation and federal officials. Autopsies will take place at the state medical examiner's office in Chapel Hill.

"It may be a few days," spokeswoman Sharon Artis said. "We have not identified any of them yet."

Bob Alexander, who lives directly across the canal from the burned home, said the students were out on the deck Saturday, getting ready to watch South Carolina's football game at Tennessee.

Alexander remembered seeing two people — a college-aged man and one young woman — dancing on the deck around 11 p.m. A short time later, South Carolina's loss to the Volunteers was over, and the Gamecocks had the neighboring Tar Heels over to commiserate. Wood and a few others from UNC stayed up late dancing and munching on leftover football snacks with their new friends.

Wood left around 1:30 a.m., but Alexander said the lights were still on at the doomed beach house as late as 2:30 a.m. He awoke to the sound of sirens a few minutes after 7 a.m.

"Flames were halfway across the channel," Alexander said. "The fire was roaring and cracking. You could already see inside the house."