Arrested for a murder that took place in August 2015, Aaron Saucedo, 23, has now been linked to the deaths of eight other people, between January and July 2016, reports the BBC.
Police have announced that they have not identified a motive, but they do believe Saucedo acted alone. Saucedo was booked on 26 additional felony counts, including a charge for a killing that hadn't previously been connected to the killer.
The 2015 victim was a 61-year-old man who dated Saucedo's mother.
While the killer was connected to that victim, his others appear more random. Many of them were ambushed in their homes in a working-class neighborhood in Phoenix. They include a 12-year-old girl and a 55-year-old woman.
Evidence against Saucedo includes surveillance video, ballistics material, and witness statements.
The Maricopa County attorney has not decided which formal charges to bring against Saucedo.
"We hope that our community will rest a little easier and that our officers will get a little more sleep knowing that the wheels of justice are finally in motion," said Police Chief Jeri Williams.
Police spokesman and Sgt. Jonathan Howard said that it was possible that other killings might eventually be tied to the suspect.
The shootings had ended in July after a massive publicity effort. Saucedo told the authorities he changed his appearance and stopped driving his same vehicle.
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