CHARLOTTE, N.C. — Inspectors returned Wednesday to a home in Ballantyne, trying to figure out what caused an explosion that killed a woman and seriously injured her husband.
The explosion was likely caused by an accidental "interior gas leak," according to a preliminary investigation.
The fire marshal did not go into any more detail about the investigation, including what sparked the explosion, at a news conference Wednesday afternoon.
An outside agency is determining what triggered it.
Fire officials urged people who smell natural gas to leave the area and call 911.
“There's a reason an odor is added to natural gas, to let you know if you smell it, there is potentially an issue,” CFD Battalion Chief Matt Westover said.
The $1.2 million house was reduced to rubble after exploding Tuesday afternoon.
[PHOTOS: $1.2 million house explodes in Ballantyne]
A woman's body was recovered from the debris around 9 p.m. Tuesday, officials said. Police identified her as 58-year-old Rania Karam.
“She was a wonderful, outgoing, personable lady -- very kind-hearted,” said Nancy Kissinger, who was a friend of Rania Karan.
Her husband, Dr. Jebran Karam, was in the emergency room Tuesday night after being pulled from the pile of debris, the CEO of Raleigh General Hospital in Beckley, West Virginia told Channel 9 reporter Joe Bruno.
(Dr. Jebran Karam)
Jebran Karam was flown to a hospital with serious injuries. Firefighters said he was conscious and alert after the explosion and was able to call 911 to help rescue crews find him.
A former owner of the home said the Karans had been on vacation before the explosion.
The windows and doors were all closed during that time.
“We're pretty sure it was a gas leak,” Carol Aaron said.
Aaron and her husband had the house built, and they returned Tuesday to help first responders in the search for the Karans.
“I have a lot of great memories from that house and will always have those, but they've lost their mother and a wife and a grandmother, and how does that compare?” Aaron said.
Piedmont Natural Gas released a statement Wednesday saying its crews checked gas lines in the area Tuesday after the explosion and no leaks were detected.
"We've determined the Piedmont Natural Gas pipelines in this area are operating safely," the company said.
The gas company is responsible for gas lines leading up to a home. Lines and appliances that use gas inside are the homeowners' responsibilities.
PIEDMONT NATURAL GAS STATEMENT:
"We are deeply saddened by the tragic loss of life. Our condolences and prayers are with those who are injured and who've lost a loved one.
Yesterday, our technicians tested and checked the Piedmont natural gas lines in the area, and no natural gas leaks on our lines were detected. We've determined the Piedmont natural gas pipelines in this area are operating safely. In an update last night, the fire department confirmed the area is safe.
Piedmont Natural Gas is committed to assisting and cooperating fully with the fire department and other agencies investigating this tragedy. The safety of this community continues to be our highest priority."
Jebran Karam is a prominent cardiologist in West Virginia. The CEO of the hospital where he works said Karam is a tremendous cardiologist, physician and advocate for his patients. Jebran and Rania Karam purchased the home in Ballantyne in 2015.
James Sheatsley, an attorney with the West Virginia Secretary of State's Office, told Channel 9 Jebran and Rania Karam have three children together.
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Officials said they began receiving numerous 911 calls about the explosion and fire just before 2 p.m., including one from Jebran Karam, who was trapped inside the house.
Firefighters got to the home along James Jack Lane off Ballantyne Commons Parkway within six minutes.
>> We first updated WSOCTV news app users with a notification just after 2 p.m. Tuesday that there had been a major explosion in Ballantyne. Download the WSOCTV news app for your smartphone and get updates on breaking stories as they come in.
Chopper 9 flew over the scene around 2 p.m. and could see flames and smoke rising from the debris pile. Wood and insulation were scattered at the site, and debris was blown into the adjacent street as well as into some surrounding trees and nearby yards.
Firefighters used a ladder truck to get closer to the flames that erupted from the explosion.
Jebran Karam, buried under the mountain of debris, was able to call 911, which helped first responders find him quickly and gave them details on where to find the Rania Karam.
Later in the day, fire officials said they were switching to a more technical and methodical search, which meant they were searching at a slower pace due to loose debris. After the Rania Karam's body was found, officials stopped their search.
(VIDEO: Home suffers heavy damage when neighbors’ house explodes)
Firefighters remained on scene overnight.
"The pressure was tremendous"
Debris from the explosion fell onto at least five nearby homes.
Neighbors and nearby businesses told Channel 9 they felt the ground shake and heard a large boom.
“I just went out for a walk. I put my Beats on, and I walked right by the house. I walked on, maybe two minutes, and through my Beats, I heard a boom!” neighbor Lorie Porter said. “Something told me to turn around and walk back, and I started turning around, and all the neighbors started to run out of their homes. And there’s debris right where I had walked, and the house was just leveled.”
Officials said several homes in the area were damaged and have been checked by firefighters.
"I felt the floor shake below, and I was nervous we were having an explosion," neighbor Sue Blackman said.
"I can't imagine being right next to it, how much you could feel it because the pressure was tremendous,” neighbor Benjamin McNeill said.
MEDIC confirmed it sent multiple units to the scene, as well as its mass casualty bus.
[ALSO READ: Firefighters think propane leak caused Caldwell County house explosion]
Fire officials said other homes in the vicinity of the explosion were safe, but those homes nearby received significant damage. MEDIC said two people living in surrounding homes were being evaluated for injuries that weren't considered life-threatening.
"I was sitting on my back patio, and I heard the boom, saw everything shake," neighbor Stephan Custer said. "I actually thought it was my house exploding. I thought the house was going to collapse and when I got far enough, I could see the plume of smoke across the street and I ran down there. I just saw it was totally obliterated."
More than 80 firefighters responded to the scene in the middle of a sweltering summer day.
“Hydration becomes an issue. We have the means to combat that. We have rehab resources here, providing water, plenty of shade. So now the challenge really becomes that our firefighters stay healthy as they continue to work,” Westover said.
Temperatures were in the upper 90s, and heat index values soared to 106 degrees Tuesday afternoon. Seven firefighters were treated on scene with IVs for dehydration and later returned to their duties.
One firefighter was taken to a hospital to be treated for dehydration, officials said.
Many people in the community came together to help the dozens of firefighters and other first responders on the scene by bringing boxes of pizza, coolers of water and Gatorade, and watermelon.
The home was 6,300 square feet and worth more than $1.2 million, according to the county's property appraisal.
Check back for updates on this developing story.