Police say a 38-year-old Idyllwild man is in custody on suspicion of murdering a 72-year-old man at his Long Beach home earlier this month.

On Thursday, Riverside County sheriff’s deputies arrested William Altpeter in Idyllwild on suspicion of the Nov. 1 murder in the 4700 block of Greenmeadow Road, near Long Beach City College’s Liberal Arts Campus, according to Long Beach police.

Search warrants carried out at Altpeter’s home and in the city of Long Beach revealed that he knew the victim, police said. They did not explain how they knew each other.

Shortly after 8:20 p.m. on Nov. 1, officers responding to the victim’s home on Greenmeadow Road found him lying inside the residence with a gunshot wound to his upper body. He was pronounced dead at the scene.

Authorities initially thought the 72-year-old man’s death was a suicide, but detectives and the Los Angeles County Medical Examiner’s Office “determined the wound was not self-inflicted,” police said.

The circumstances leading up to the shooting, along with a motive, remain under investigation.

Altpeter was being held in Long Beach jail on $3 million bail.

Anyone with any information regarding the incident is urged to contact LBPD homicide detectives Eric Thai or Kelsey Myers at 562-570-7244.