PHOENIX - The 23-year-old man accused of carrying out a string of shootings that crisscrossed the Valley and left nine people dead proclaimed his innocence before a judge on Monday night.

Aaron Juan Saucedo is facing 26 new charges that include eight first-degree murder charges, aggravated assault and drive-by shootings. He is being held without bond.

After the judge read out the charges he faces, Saucedo exclaimed, "I'm innocent."

Saucedo's next court date is Monday.

The man was arrested in April for a different case involving the shooting death of his mother's boyfriend in 2015. Investigators said they connected Saucedo to the string of shootings after receiving tips from the public and carefully reviewing evidence.

MORE: Phoenix PD: Aaron Saucedo arrested for Serial Street Shootings

Maricopa County Attorney Bill Montgomery said court documents surrounding the case are being sealed to protect the integrity of the case.

"That information at this point in time should not be made public because it's an ongoing investigation," he said.

12 News has learned Saucedo was a student in the Phoenix Union High School District and attended Phoenix's North High School as a sophomore from 2009 to 2010 and then transferred to Central High School, only to withdraw after one semester in January 2011.

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A spokesperson says a month later, his transcripts were sent to a charter school.

Back in 2015, Saucedo had a run-in with the law for running a red light. The man was working as a public bus driver for the City of Phoenix at the time of the offense and pleaded guilty.

MAP: See the Serial Street Shootings mapped out across Phoenix%INLINE%