Authorities are investigating a fire that destroyed the majority of a 7,000-square foot house in Fort Bend County on Friday morning.

The Fort Bend County Sheriff's Office says the fire broke out around 8 a.m. Friday at the home in the 10400 block of Pebblecreek Crossing in Cinco Ranch near Fulshear.

"We were making breakfast for our daughter, about 7:30 and noticed all of the people out front and came running out, it was blazing probably two stories above the house, it is the biggest house on the neighborhood," said Cliff Halphen, neighbor.

Firefighters said the home was completely engulfed with flames when they arrived. The Fulshear Fire Department was the first on the scene and they immediately called for backup when they saw the size of the home.

"Seven departments arrived from surrounding areas to bring in their ladder trucks because the structure was so big, 7200 square foot, multi-room house," said Lt. Robbie Baker of the Fort Bend County Fire Marshall's office.

Officials told Local 2 the home was worth $1.5 million. Four luxury cars in the garage were also destroyed by the flames.

"It looked like some things were exploding in the house, as soon as they got it simmered down it would erupt back up," said Halphen.

Officials said a husband and wife and their two daughters were asleep when the fire started. The family of four and their three dogs all made it out of the house safely.

"One of the neighbors was taking out the trash, saw the smoke and alerted the people to come out, they were still in their pajamas and unfortuntatly they pretty much lost everything," said Halphen.

The Fort Bend County Fire Marshal said three-quarters of the house was damaged, so the home is likely a total loss.

The fire marshal's office is investigating what caused the fire to start.

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