GLENDALE, Ariz. — Police say an Arizona man fatally beat his stepfather, a disabled veteran who uses an electric wheelchair, reports CBS affiliate KPHO.

Investigators say that on Tuesday afternoon, suspect Heath Allen McConkey demanded the 72-year-old victim get out of his hospital-style bed. When the victim said no, 46-year-old McConkey "became enraged" and started punching the victim in the face with both hands, investigators wrote in court documents.

McConkey then allegedly pulled the victim, whose name has not been released, off the bed and onto the ground and continued to punch and kick him, investigators said.

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Allegedly "exhausted from beating the victim," McConkey soon passed out on the floor, police said. His mother arrived home not long after that and found the two men in a pool of blood.

She called police and McConkey was arrested.

McConkey is being held in jail on a secured bond of $1 million.