HOUSTON (CBSDFW/AP) – A Houston police officer was shot twice in the head and died Tuesday before a SWAT team was dispatched to the scene, where the suspected shooter — Elmer Manzano, 51 — was arrested, authorities said.

Elmer Manzano – 2003 mugshot (credit: Dallas County Jail)

Sgt. Harold Preston, a 41-year veteran of the department was killed. Preston had plans of retiring from the force soon.

Another officer, Sgt. Courtney Waller was shot in the arm and is expected to survive.

Police Chief Art Acevedo said a Good Samaritan, who is a former gang member helped both injured officers.

“He saw a man who needed help,” said Acevedo. “He’s a hero.”

Sgt. Harold Preston (credit: Houston PD)

The shooting unfolded around 7:55 a.m. at the Richmond Manor apartments in the 2600 block of Holly Hall and El Mundo, near Highway 288.

The circumstances that led to the shooting in the southwest part of the city were unclear and more information was not immediately available.

Police had warned people to avoid the area but said around 10:30 a.m. that the confrontation was over.

Manzano was shot in the abdomen and taken to the hospital in stable condition.

Acevedo said he has an extensive rap sheet, including a charge for animal cruelty.

Lt. Gov. Dan Patrick issued the following statement about Preston’s death:

“Earlier today, Sgt. Harold Preston was gunned down in the line of duty protecting his community. Sgt. Preston served Houston for 41 years, a testament to his remarkable dedication to service. Jan and I will be praying for Sgt. Preston’s family, friends and the Houston Police Department, and we ask that you join us in doing the same. We also pray for the quick recovery of Officer Courtney Waller, who was wounded in the same incident. It’s vitally important that Texans remember that law enforcement officers risk their lives for us every day to keep our communities safe.”

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