He then killed his wife and two daughters at the family home and went to the apartment of the man with whom he believed he had an affair, said Sgt. Tommy Thompson of the Phoenix Police Department.
There, he shot down the man and injured two others, he said.
His wife, Dasia Patterson, 29, and their daughters Mayan Smith, 7, and Nasha Smith, 5, were found dead at the family home, police said.
His 3-year-old daughter was hiding under a bed when police arrived and was not injured, Thompson said. The suspect told the police that he had chosen not to kill her because she "remembered to himself," reported the affiliate, citing court documents.
Police said the eldest daughter had died as a result of violent trauma, and the suspect told investigators that he would have killed her because she was crying.
Patterson's parents said they were devastated and had trouble accepting the loss.
"As we try to manage our deepest pain, we focus on the well-being of her only surviving daughter, age 3. She has just lost her mother and sisters, and we want nothing more than to She's with her family now. "
A second crime scene
After killing his family, Smith drove into a building in Phoenix and shot dead Ron Freeman, 46, accused of having an affair with his wife, police said.
In addition to Freeman, he allegedly shot two other people at home – a man and a woman – who were not identified. The 47-year-old woman is in critical condition, while the 33-year-old man was seriously injured.
Police received a call about the shooting on the apartment and found the car of the suspect who was running away on their arrival, Thompson said.
"The car was stopped a short distance from the scene … and the suspect, Austin Smith, was arrested without incident," he added.
At the scene of the second shooting, one of the victims expressed concern for the suspect's family. When the police conducted a welfare check with the suspect's family, they found his deceased wife and two children.
During an interview with investigators at the Phoenix Police Headquarters, the suspect said, "The reason he shot these people down is because in the eyes of God it was normal that 39; he deals with someone in this way, "Thompson said.
"He admitted the crimes and said that he thought his wife, Dasia, had cheated on Ron, Austin said God had told him to do what he had done," he said. .
Smith was incarcerated in Maricopa County Jail and charged with four counts of first degree murder, two counts of attempted first degree murder and three counts of aggravated assault.
The information about his lawyer was not immediately available.