ROLESVILLE (WTVD) -- After three weeks and eight agencies working on the case, Rolesville Police are closing the investigation into a house fire and calling it a murder-suicide.On the morning of Dec. 11, a fire sparked inside a home in the 6200 block of Saddle Drive. Search warrants unsealed Monday detail how a Rolesville police officer and Wake County EMS described the scene. The officer reported seeing smoke coming from a vent on the north side of the home.The warrants detail how an officer ran into a neighbor standing outside who told him, "she's in there with her babies."The officer could hear an alarm sounding off inside the home and began kicking the front door. It wasn't until Rolesville firefighters arrived with tools that they were able to get the door open.Inside they found Kristy Bryan, 39, and her 3-year-old son Tyler, dead in the master bedroom. They found his twin brother on the other side of the home, the lone survivor of the fire who is now out of the hospital.Investigators found a gas can on scene and determined that the fire started in the master bedroom and in a news release said this "was the result of an intentional spread from an ignitable liquid." There was no forced entry or any signs of struggle in the home.Kristy Bryan lived in the home with her husband, Derek Bryan, and their three children. Her husband had already left for work and their oldest child was in school."What brought Mrs. Bryan to the point of doing this, I think, unfortunately there are certain things we don't have answers to," said Wake County District Attorney, Lorrin Freeman.Freeman said investigators chose to keep the details of the investigation from the public for the last three weeks, because they wanted to make sure they were thorough before quickly labeling this a murder-suicide of a mother and small child.The newly unsealed search warrants detail a number of items found in the home that helped lead to that conclusion. Those include a red gas can, a bottle of pills, another melted bottle of pills, several plastic zip ties and the end of a lighter.As far as what exactly happened before the fire, we will have to wait another few weeks for the autopsy and toxicology reports.Until then, Derek Bryan and his two surviving children remain in the community's thoughts."We appreciate the full cooperation of Mr. Derek Bryan and the entire family during the course of the investigation. Please continue to keep the family in your thoughts and prayers," Rolesville Police Chief, Bobby Langston said."I think anytime that you live in a community like that that's a safe community where people know each other, these types of cases are particularly tough," Freeman said.The Bryan family also released a statement:"The family is grieving the loss of their loved ones and request privacy during this most difficult time."