SOCASTEE, SC (WBTW) –  Horry County Fire Rescue crews say a 70-year-old woman is dead after a house fire in Socastee early Monday morning.

The fire was in a mobile home on Keith Street in Socastee, just outside Myrtle Beach. Investigators don’t know how the fire started, but they do know it began in the home’s living room.

Though they don’t know specifically how it started, Captain Mark Nugent with Horry County Fire Rescue confirms that officials have ruled out any malicious activity.

Captain Nugent says the call came in Monday morning around 2 a.m. He adds rescue crews responded within minutes and worked to put out the fire and to rescue people inside for about an hour.

Four adults were inside the home, and Nugent says one died.

Horry County Coroner Darris Fowler says 70-year-old Maria Vaca of Myrtle Beach died from smoke inhalation.

Another person who was inside the home was taken to the hospital, but is expected to be ok.

Investigators are working to try to find out what caused the fire. Horry County Police also responded to the scene.

Nugent credits a smoke alarm inside the home as the tool that likely saved the other three people. A post from Horry County Fire Rescue’s Facebook page says records confirm members of the fire department actually installed three smoke alarms in the home during a Smoke Alarm Blitz about a month before.

“Where the organization is Heart Broken that a loss of life occurred as a result of the tragic fire, we can take comfort in knowing the recently installed Smoke Alarms saved three lives. We were told by one of the survivors that the Smoke Alarms installed by the firefighters several weeks ago woke everyone up, allowing them to get out of the home, saving their lives,” the post states.