Tracking a serial killer is nothing new for the Phoenix Police Department.
Ten years ago, detectives were working two deadly serial killer cases at the same time.
The Baseline Killer and Serial Shooter cases showed what a massive undertaking these types investigations are, involving a tremendous amount of manpower.
Detectives, lab personnel, and ballistics experts work around the clock.
Retired Phoenix police Sgt. Andy Hill gave constant updates on the Baseline Killer and Serial Shooter cases back in 2006.
Hill has first-hand knowledge about what's involved in catching a serial offender, like the one now terrorizing the Valley.
"The suspect or suspects, in this case, have already made a mistake," said Hill. "They've already left evidence somewhere, already told somebody, somebody in their family knows something about this. That information is out there."
So far, at least 7 people have been killed this year in a series of shootings, from March until June.
Most of the killings took place on west side of Phoenix, but now, the investigation has expanded to the east Valley, possibly providing new clues.
"It might show where the suspect or suspects live or started," said Hill. "If they live close to there, work close to there, and may show they may have changed areas simply because they wanted to get to a different place ,and throw something with the investigation off, somehow."
A multi-agency task force has been set up to help solve the serial street shooter case. as Phoenix PD and other agencies work together to compare leads and evidence.
Hill said that everyone working on the case knows what's at stake.
"Every investigator doesn't want to see there be another victim," said Hill.
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