Dionisio Garza, 25, drove into Houston from California on Saturday to visit friends in the area, police said. He later broke into a tire shop and spent the night there.
On Sunday, Garza came out of the shop and confronted people washing cars, police said. Eugene Linscomb, 56, was among them. Police say Garza shot Linscomb in the neck, killing him.
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Garza then went back into the shop, grabbed an AR-15 assault rifle and started shooting at passing cars and officers arriving at the scene. Two police officers were injured and several vehicles were shot at.
One of the bullets Garza fired hit a line to a nearby gas station, igniting the fire.
Police say Garza fired 212 rounds before SWAT officers arrived at the scene, set up a perimeter and fatally shot him.
Police say after the shooting, they found random piece of paper and writing on the walls inside the tire shop. While they didn't appear to be terror related, they seemed to be the writing of a person in a "mental health crisis." Garza's family said he was discharged from the military in 2013 and was battling a bout of depression.
Police also determined that another man they initially thought was a second suspect turned out to be a nearby resident who tried to stop Garza. Police said John Wilson was outgunned and when he tried to leave, he was shot in the leg. He remains in ICU, where he is listed in stable condition.
Three other people were wounded in the incident: a 59-year-old, a 24-year-old man and a 50-year-old man. All three are in stable condition and did not suffer any life-threatening wounds.
Interim Houston Police Chief Martha Montalvo also acknowledged that miscommunication between two police units prompted officers to leave a backpack at the scene. Montalvo said the evidence should've been collected and the incident won't happen again.