CHARLOTTE, N.C. -- The 911 calls from a massive home explosion that killed a woman and severely injured her husband have been released. Additionally, incident has been ruled an accident.

Previously reported: 

• Woman Dead, Man Seriously Injured in Ballantyne Home Explosion
• Fire Marshal: Natural Gas Leak Likely Caused Deadly Home Explosion

Charlotte fire investigators say natural gas accumulated inside the million-dollar home several days before the explosion while the owners were away on vacation.

Moments after Rania and Jebran Karam returned home, the house exploded, killing Rania and leaving Jebran buried in the rubble.

Investigators were not able to pinpoint exactly what caused the leak or led the gas to ignite.

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