HOUSTON - Houston Police released new details about Sunday's mass shooting in west Houston during a press conference Tuesday.

According to investigators, the suspect, Dionisio Garza III, fired 212 rounds during the shooting rampage in a neighborhood off of Memorial Drive.

Police say that Garza came from California and arrived on Saturday to see some friends. They believe that the shooting location was random.

The suspect broke in to a tire shop and stayed there the day before the shooting. Police believe he intentionally turned off his phone and "went off the grid" at 4 p.m. Saturday.

Garza came out of the tire shop and confronted victim Eugene Linsomb and shot him. Linscomb died at the scene. The suspect then retrieved an AR-15 and shot at passing cars and police vehicles. He struck a line to the gas station, which then caught on fire.

"We believe his military training and his location, he felt safe there," said Lt. John McGalin. "Had access to three corners. Didn't have to worry about anyone coming up behind him. There just seems to be no rhyme or reason to why he picked that location."

John Wilson, who was initially believed to be a second shooter, was a resident in the area and came out to offer assistance. He was out-gunned by the suspect and was shot in the leg. He is expected to survive.

A total of eight people were shot, including the gunman. An HPD sniper fired four rounds, including the kill shot.

"At the scene, we found some random writings on the walls he wrote on paper, nothing of consequence, doesn't appear to be terrorism, just appears to be someone who was in mental health crisis at this time," said McGalin.

Dionisio Garza III
Dionisio Garza III

Garza's stepmother Cathy Garza spoke to KHOU 11 News over the phone. She says the family is devastated by what happened.

"They're taught to be tough and to not be weak," said Garza. "From the outside, it seemed like he was doing okay, but I think on the inside, he was just slowly crumbling, and it got to the point where he just wasn't making sense. He was kind. He had friends. He got along well with others. He was a great kid. Our hearts just go out to the families. We feel for them. It's not, it just wasn't him that day. He was not that person."

HPD Interim Chief Martha Montalvo thanked residents who opened their doors to strangers during the shooting and said that the death toll could have been much worse. Residents saw the shooter from home and alerted police.

Police say that there was no terrorism link to the event but that Garza was suffering from a mental health crisis. HPD urged the public to remain vigilant about former military members that may need help when they return home.