PHOENIX (KSAZ) - Eight separate shootings have left seven people dead and two wounded.
That's the latest in the serial shooter case that has the Valley on edge. The investigation is ramping up after police connected four more cases to the shooter(s).
Phoenix police also released a sketch of the suspect in the case, but so far no arrests have been made. Authorities believe the shootings are connected but aren't releasing what ties the cases together.
A forensic psychiatrist is shedding light on who the person may be.
"There's no doubt in my mind that the person or persons who are responsible for this work ultimately be apprehended it's not a question of will, it's a question of when," said Dr. Steven Pitt.
Dr. Pitt says the killing of seven people in a string of shootings in and around Maryvale is the work of a serial killer. That is defined as someone who murders three or more people in a 30-day period with an inactive period between each murder.
"The area that's being targeted, if I had to bet dollars to donuts it would be that this individual is certainly familiar with the area," he said.
Tuesday police released a composite sketch of the possible suspect and added four new cases to the original four. In all, seven people including a 12-year-old girl have been killed, several others injured. Pitt says what is most concerning is the random nature of the victim selection.
"It always starts with the victimology, but what I also suspect is going on is that they forensically linked these cases together, what that forensic link is, I don't know. They are wisely keeping a lid on that, but I suspect they have a lot more information that's tying these cases together," said Pitt.
Pitt says serial killers typically work alone, but there could be two people doing this or more. He says they typically follow the news coverage of the case closely. He believes good police work will catch those responsible, but most of all people coming forward from the community.
"At the end of the day this individual or person responsible are people who are someone's significant other, someone's co-worker, someone's family member, someone's friend," he said.
Silent Witness is offering a $30,000 reward for tips leading to an arrest; you can call them at 480-WITNESS.