A woman and her three children are safe after someone set their north Harris County home ablaze the fire marshal's office said.

Senior Investigator Bryan Holmes with Harris County Fire Marshal's Office said the family was staying at a relative's home for the week.

Around 1:30 a.m. the Aldine fire district was called to the home in the 800 block of Hillrock Bluff Circle, Holmes said. 

Firefighters said they discovered an incendiary device was used to set the back of the home on fire.

"There is moderate damage to the back room of the residents. It suffered severe damage the exterior of the residents' home suffered minor damage," Holmes said.

He went on to say the family's den was destroyed.

Holmes would not reveal what sort of device was used or why the family may have been targeted.

"While the case is still under investigation, we do know that no one was at the home at the time of the fire," said Lieutenant Gustavo Lopez, with the Harris County Fire Marshal’s Office.

But the woman who owns the home did not want to go on camera, but revealed her daughter was also shot at last week.