Scottsdale Police said that Knowlton and his father were found lying on the floor, covered in blood inside a senior living facility, USA Today reported.
Police said Knowlton stopped breathing as he was being handcuffed and was taken to the hospital where he was pronounced dead just after midnight. The cause of death in unknown at this time. Police also said Knowlton was found with drug paraphernalia on him.
Officers were responding to a 911 call from a woman who said her son was attacking her and her husband. According to USA Today, the woman also appeared to have been beaten when they arrived. The parents are reportedly in a stable condition.
Knowlton worked as an executive with multiple Arizona-based companies for 14 years. Before his death, Knowlton was the senior vice president of global sales and international at Massage Envy.