A Phoenix family of five is dead after one family member shot and killed his parents and two sisters, PEOPLE confirms.



According to Phoenix police, early Tuesday morning two 911 calls were received asking for help. The calls, made by Kimberly, 18, and Kaitlin Buckner, claimed Alex Buckner had shot them.



Minutes later, officers arrived at the home only to find it engulfed in flames, Sgt. Trent Camper of the Phoenix Police Department tells PEOPLE. Officers heard shots fire from inside the home and saw the victims calling for help from a bedroom window, according to Crump.



When they entered the home, rescuers were able to pull 18-year-old Kaitlin out of the fire. Kaitlin was taken to a local hospital where she died.



As their search continued, rescuers found two more victims with gunshot wounds. They were the bodies of Vic and Kimberly Buckner, Alex's parents.



Authorities continued searching the home until they found the alleged gunman, Buckner, in a room holding a gun, Crump says.



The 26-year-old pointed his gun towards authorities and after a brief standoff was shot and killed.



As they continued to search the home, rescuers discovered the body of six-year-old Emma, Buckner's youngest sister. She had been shot in a bedroom, Crump tells PEOPLE.



Crump cannot confirm the cause of death for the victims because the bodies are with the medical examiner.



All four victims were shot and inahled a heavy amount of smoke, Crump says.



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According to Crump, Buckner had a history of drug abuse but had been treated. He said there is no known record of the 26-year-old having mental illness issues. Buckner has no known criminal record in Arizona.



Buckner allegedly started the fire with an accelerant in the den of the home, Crump tells PEOPLE.



According to local new stations, Buckner was arrested in 2012 for petty larceny and resisting an arrest.



A GoFundMe page has been set up to help pay for the family's funeral costs.