The guard was taken to the hospital and was being treated for at least one gunshot wound.
Glendale Police Sergeant Jay O'Neil said the suspect and security guard, who was not in a uniform, began fighting after the officer confronted him for shoplifting.
"At some point during the struggle, the suspect produced a weapon." said O'Neil. "He fired several rounds at the security guard and struck him at least one time."
A second, uniformed security guard was called prior to the struggle.
The uniformed guard was able to use his Taser on the suspect, who then attacked with a knife. The suspect also assaulted the plain-clothes guard.
O'Neil described the suspect as a Hispanic male in his late 30's to early 40's; 5-foot-5 around 150 lbs. with short, dark hair. He was last seen wearing a charcoal colored shirt that was unbuttoned, long gray shorts and white tennis shoes.
The uniformed guard received both a bullet and knife wound. The other received minor injuries. None were life-threatening.
Glendale Police called this a sad reminder of how dangerous a shoplifting situation can be and warned residents to call 911 if they witness a shoplifting rather than get involved in a potentially life threatening situation.