PHOENIX (KSAZ) - Neighbors say they believe police were casing 22-year-old, Aaron Juan Saucedo's home for days earlier this week.
"I dont know what they were looking for, but there was a lot of dark, unmarked, tinted windows and this was for days," said Jose Guzman.
He was arrested Wednesday, now charged with first degree murder.
Court documents say he was behind the murder of his mother's boyfriend back in August of 2015.
The man was found shot to death on Montebello Avenue.
Court records indicate that nearly three weeks after the shooting, Saucedo pawned the gun used in the crime. It was bought by someone else.
Police retrieved it from the new owner and matched the shell casings to the ones which were found at the scene.
Guzman was shocked to hear his neighbor, who he saw often, is now accused of murder.
"You know it's a good neighborhood, quiet, family kept to themselves," said Guzman.
He says Saucedo was living here on 10th Street with his mother.
"My heart goes out to her because I'm sure she's shocked as anyone else," said Guzman.
Neighbors say police took evidence from the home including a car that Saucedo reportedly drove.
"A black BMW, that's been in the news," said Guzman.