Police in Washington state cleared a convicted felon as a suspect Monday in the shooting death of his girlfriend's 4-year-old son after a coroner's report found that the boy accidentally shot himself.

The boy, identified Monday as Dwayne Kerrigan, was shot Sunday morning at the woman's home in Sedro-Woolley, in northern Washington. He died at Skagit Valley Hospital in Mount Vernon.

Police initially declared Trevor Braymiller, 25, the boyfriend of Dwayne's mother, a suspect in a homicide investigation and launched a search for him across Skagit County. Braymiller turned himself in to police Monday, NBC station KING of Seattle reported.

Later Monday, authorities said an autopsy made it clear that Dwayne shot himself by accident.

Police found a gun, believed to be the weapon that killed the boy, a few doors down from the scene. Because the gun belonged to Braymiller, he still likely faces charges because, as a convicted felon, he isn't allowed to possess a weapon.

Police didn't say why Braymiller initially fled the area.

A former co-worker, Rueben Dreyer, told KING that Braymiller asked for a ride out of town shortly after the incident Sunday.

"He said he went outside in the garage to smoke a cigarette, and he heard a boom and went back into the house, and (Dwayne) wasn't moving," said Dreyer, who said Braymiller seemed scared and shaken but insisted he didn't shoot the boy.

"He must have gotten up and got (the gun). That's all he told me," Dreyer said.

In a statement, Dwayne's family said his mother and his father had been involved in a custody dispute.

"Dwayne's father, Chaz, has been trying to be a part of his son's life for quite a while now. He and the mother have been involved in an ongoing custody dispute and were about to enter into mediation for visitation rights," the statement said.

"Now he will never get the opportunity to see his SON again. We love and miss Dwayne very much."

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