The suspect in Thursday's officer involved shooting is now under guard at an undisclosed hospital.
Andrew Luna, 22, was shot once in the arm by an El Cajon police sergeant, after Luna allegedly came after the sergeant with a knife.
Residents in the 1700 block of Pepper Hill Drive called police because the thought Luna was acting suspiciously.
The knife-wielding suspect was a threat to both the officer and residents, whom he could have stabbed, said Lt. J.D. Arvan. Officials believed Luna could have thrown the knife at someone, or lunged at them.
Court records obtained by NBCSanDiego reveal Luna has been arrested and charged at least six times in the past four years, for narcotics and DUI violations. Those records show that Luna pleaded guilty to most of those charges, and then repeated violated probation.
Keep up to date on breaking news: Download our improved iPhone app, follow us on Twitter @nbcsandiego, fan us on Facebook, sign up for our breaking news e-mail alerts or text SDBREAKING to 622339 to receive text messages for local breaking news. (For more info, text HELP. To end, text STOP. Message and data rates may apply.)