PHOENIX -- An embattled Tempe police officer resigned from the force on Monday, the department confirmed.
Officer Garrett Michael Peterson, 30, resigned the same day he made an appearance in court after a Saturday car chase that saw speeds more than 120 mph.
"It's a shock to all of here at the Tempe Police Department," Tempe Police Sgt. Mike Pooley said. "Many of us have worked with (Peterson). Many of us know him very well and we had no idea this was happening to him."
Poole said Peterson was hired in May 2007 and was a good officer.
"He was a very good employee," he said. "We're very saddened by this. We're trying to make sense of it. We're trying to figure out what turned around in his life to make him have these poor decisions."
After resigning, Peterson allegedly led Arizona Department of Public Safety officers on a brief chase on Interstate 8 near Yuma. DPS said Peterson was driving at speeds of more than 90 mph and, after making several turns, hit a commercial truck head-on.
Peterson was hospitalized with a minor head injury. DPS said impairment may have been a factor.
Tempe police said Peterson has been detained by DPS and is in their custody.
Peterson was charged with felony endangerment, threatening and intimidating, driving under the influence, felony flight and reckless driving in the first chase. Bond was set at $10,000 with a Dec. 20 status conference and Dec. 24 preliminary hearing.
Peterson doesn't have an attorney yet.
The Associated Press contributed to this report.