The Phoenix Police Department has identified the detective killed Monday as John Hobbs, 43. He was a 21-year veteran of the department.
Police Chief Daniel Garcia said Hobbs is survived by his wife and children, aged 10, 8, and 6.
Hobbs was a member of the Major Offender’s Bureau and was trying to apprehend William Thornton, 28.
Thornton apparently realized the undercover officers were following him and fled in a car, causing a three-vehicle accident at the intersection of 43rd Avenue and Bethany Home Road. He then exchanged gunfire with officers outside of a check-cashing business.
Hobbs was hit and injured but continued to pursue the suspect, returning fire and hitting Thornton several times. A third officer confronted Thornton and shot him to death.
Garcia stressed that Thornton was a known felon who had been released from prison in January and suspected in an attempted murder in February.
"He walked up to an individual and shot him, point blank in the chest. This is our suspect. This is who we were looking for. This is a violent felony offender," Garcia said.
Officials are not releasing the name of the second detective shot, only saying he’s 44 years old, a nine-year veteran of the force, and in stable condition.
Garcia said at an emotional news conference Tuesday morning he could not be more proud of his officers.
“It’s amazing to me that in such a tragedy, I’m constantly besieged by e-messages and text mails from my troops, reaching out to me, asking me if I’m doing okay," he said.
KJZZ's Mark Brodie and Stina Sieg contributed to this report.
Updated 3/4/2014 at 12:13 p.m.